Repository: seanmonstar/reqwest (language: rust)

Issue:
Should the builder hold an error to the end?
In v0.7, the `RequestBuilder` was changed to return an `Result` immediately whenever any of the builder methods could fail. This means that there is a lot of `?`, or more painful, `.unwrap()` when the best action is to just panic.

Considering that there is now a `Request` type where one can set all the properties of a request in an infallible way, and serialize JSON before hand or what-have-you, the `RequestBuilder` should have a design that makes it the easiest to use. It may make sense to move the result back to when the builder is consumed, so that there is only ever 1 `Result` to deal with.


Discussion / hints:

Fix patch:
diff --git a/examples/async.rs b/examples/async.rs
index 3cafb5f3b..222acde1e 100644
--- a/examples/async.rs
+++ b/examples/async.rs
@@ -18,11 +18,11 @@ error_chain! {
     }
 }
 
-fn main() {
-    let mut core = tokio_core::reactor::Core::new().unwrap();
-    let client = Client::new(&core.handle()).unwrap();
+fn run() -> Result<()> {
+    let mut core = tokio_core::reactor::Core::new()?;
+    let client = Client::new(&core.handle());
 
-    let work = client.get("https://hyper.rs").unwrap()
+    let work = client.get("https://hyper.rs")
         .send()
         .map_err(|e| Error::from(e))
         .and_then(|mut res| {
@@ -36,5 +36,8 @@ fn main() {
             io::copy(&mut body, &mut io::stdout()).map_err(Into::into)
         });
 
-    core.run(work).unwrap();
+    core.run(work)?;
+    Ok(())
 }
+
+quick_main!(run);
diff --git a/src/async_impl/client.rs b/src/async_impl/client.rs
index a6203bea9..5a76acd56 100644
--- a/src/async_impl/client.rs
+++ b/src/async_impl/client.rs
@@ -31,6 +31,7 @@ pub struct Client {
 /// A `ClientBuilder` can be used to create a `Client` with  custom configuration:
 pub struct ClientBuilder {
     config: Option<Config>,
+    err: Option<::Error>,
 }
 
 struct Config {
@@ -45,23 +46,25 @@ struct Config {
 
 impl ClientBuilder {
     /// Constructs a new `ClientBuilder`
-    ///
-    /// # Errors
-    ///
-    /// This method fails if native TLS backend cannot be created.
-    pub fn new() -> ::Result<ClientBuilder> {
-        let tls_connector_builder = try_!(TlsConnector::builder());
-        Ok(ClientBuilder {
-            config: Some(Config {
-                gzip: true,
-                hostname_verification: true,
-                proxies: Vec::new(),
-                redirect_policy: RedirectPolicy::default(),
-                referer: true,
-                timeout: None,
-                tls: tls_connector_builder,
-            })
-        })
+    pub fn new() -> ClientBuilder {
+        match TlsConnector::builder() {
+            Ok(tls_connector_builder) => ClientBuilder {
+                config: Some(Config {
+                    gzip: true,
+                    hostname_verification: true,
+                    proxies: Vec::new(),
+                    redirect_policy: RedirectPolicy::default(),
+                    referer: true,
+                    timeout: None,
+                    tls: tls_connector_builder,
+                }),
+                err: None,
+            },
+            Err(e) => ClientBuilder {
+                config: None,
+                err: Some(::error::from(e)),
+            }
+        }
     }
 
     /// Returns a `Client` that uses this `ClientBuilder` configuration.
@@ -75,7 +78,12 @@ impl ClientBuilder {
     /// This method consumes the internal state of the builder.
     /// Trying to use this builder again after calling `build` will panic.
     pub fn build(&mut self, handle: &Handle) -> ::Result<Client> {
-        let config = self.take_config();
+        if let Some(err) = self.err.take() {
+            return Err(err);
+        }
+        let config = self.config
+            .take()
+            .expect("ClientBuilder cannot be reused after building a Client");
 
         let tls = try_!(config.tls.build());
 
@@ -105,28 +113,25 @@ impl ClientBuilder {
     ///
     /// This can be used to connect to a server that has a self-signed
     /// certificate for example.
-    ///
-    /// # Errors
-    ///
-    /// This method fails if adding root certificate was unsuccessful.
-    pub fn add_root_certificate(&mut self, cert: Certificate) -> ::Result<&mut ClientBuilder> {
-        let cert = ::tls::cert(cert);
-        try_!(self.config_mut().tls.add_root_certificate(cert));
-        Ok(self)
+    pub fn add_root_certificate(&mut self, cert: Certificate) -> &mut ClientBuilder {
+        if let Some(config) = config_mut(&mut self.config, &self.err) {
+            let cert = ::tls::cert(cert);
+            if let Err(e) = config.tls.add_root_certificate(cert) {
+                self.err = Some(::error::from(e));
+            }
+        }
+        self
     }
 
     /// Sets the identity to be used for client certificate authentication.
-    ///
-    /// This can be used in mutual authentication scenarios to identify to a server
-    /// with a Pkcs12 archive containing a certificate and private key for example.
-    ///
-    /// # Errors
-    ///
-    /// This method fails if adding client identity was unsuccessful.
-    pub fn identity(&mut self, identity: Identity) -> ::Result<&mut ClientBuilder> {
-        let pkcs12 = ::tls::pkcs12(identity);
-        try_!(self.config_mut().tls.identity(pkcs12));
-        Ok(self)
+    pub fn identity(&mut self, identity: Identity) -> &mut ClientBuilder {
+        if let Some(config) = config_mut(&mut self.config, &self.err) {
+            let pkcs12 = ::tls::pkcs12(identity);
+            if let Err(e) = config.tls.identity(pkcs12) {
+                self.err = Some(::error::from(e));
+            }
+        }
+        self
     }
 
     /// Disable hostname verification.
@@ -139,14 +144,19 @@ impl ClientBuilder {
     /// significant vulnerability to man-in-the-middle attacks.
     #[inline]
     pub fn danger_disable_hostname_verification(&mut self) -> &mut ClientBuilder {
-        self.config_mut().hostname_verification = false;
+
+        if let Some(config) = config_mut(&mut self.config, &self.err) {
+            config.hostname_verification = false;
+        }
         self
     }
 
     /// Enable hostname verification.
     #[inline]
     pub fn enable_hostname_verification(&mut self) -> &mut ClientBuilder {
-        self.config_mut().hostname_verification = true;
+        if let Some(config) = config_mut(&mut self.config, &self.err) {
+            config.hostname_verification = true;
+        }
         self
     }
 
@@ -155,14 +165,18 @@ impl ClientBuilder {
     /// Default is enabled.
     #[inline]
     pub fn gzip(&mut self, enable: bool) -> &mut ClientBuilder {
-        self.config_mut().gzip = enable;
+        if let Some(config) = config_mut(&mut self.config, &self.err) {
+            config.gzip = enable;
+        }
         self
     }
 
     /// Add a `Proxy` to the list of proxies the `Client` will use.
     #[inline]
     pub fn proxy(&mut self, proxy: Proxy) -> &mut ClientBuilder {
-        self.config_mut().proxies.push(proxy);
+        if let Some(config) = config_mut(&mut self.config, &self.err) {
+            config.proxies.push(proxy);
+        }
         self
     }
 
@@ -171,7 +185,9 @@ impl ClientBuilder {
     /// Default will follow redirects up to a maximum of 10.
     #[inline]
     pub fn redirect(&mut self, policy: RedirectPolicy) -> &mut ClientBuilder {
-        self.config_mut().redirect_policy = policy;
+        if let Some(config) = config_mut(&mut self.config, &self.err) {
+            config.redirect_policy = policy;
+        }
         self
     }
 
@@ -180,28 +196,27 @@ impl ClientBuilder {
     /// Default is `true`.
     #[inline]
     pub fn referer(&mut self, enable: bool) -> &mut ClientBuilder {
-        self.config_mut().referer = enable;
+        if let Some(config) = config_mut(&mut self.config, &self.err) {
+            config.referer = enable;
+        }
         self
     }
 
     /// Set a timeout for both the read and write operations of a client.
     #[inline]
     pub fn timeout(&mut self, timeout: Duration) -> &mut ClientBuilder {
-        self.config_mut().timeout = Some(timeout);
+        if let Some(config) = config_mut(&mut self.config, &self.err) {
+            config.timeout = Some(timeout);
+        }
         self
     }
+}
 
-    // private
-    fn config_mut(&mut self) -> &mut Config {
-        self.config
-            .as_mut()
-            .expect("ClientBuilder cannot be reused after building a Client")
-    }
-
-    fn take_config(&mut self) -> Config {
-        self.config
-            .take()
-            .expect("ClientBuilder cannot be reused after building a Client")
+fn config_mut<'a>(config: &'a mut Option<Config>, err: &Option<::Error>) -> Option<&'a mut Config> {
+    if err.is_some() {
+        None
+    } else {
+        config.as_mut()
     }
 }
 
@@ -216,21 +231,21 @@ fn create_hyper_client(tls: TlsConnector, proxies: Arc<Vec<Proxy>>, handle: &Han
 impl Client {
     /// Constructs a new `Client`.
     ///
-    /// # Errors
+    /// # Panics
     ///
-    /// This method fails if native TLS backend cannot be created or initialized.
+    /// This method panics if native TLS backend cannot be created or
+    /// initialized. Use `Client::builder()` if you wish to handle the failure
+    /// as an `Error` instead of panicking.
     #[inline]
-    pub fn new(handle: &Handle) -> ::Result<Client> {
-        ClientBuilder::new()?.build(handle)
+    pub fn new(handle: &Handle) -> Client {
+        ClientBuilder::new()
+            .build(handle)
+            .expect("TLS failed to initialize")
     }
 
     /// Creates a `ClientBuilder` to configure a `Client`.
-    ///
-    /// # Errors
-    ///
-    /// This method fails if native TLS backend cannot be created.
     #[inline]
-    pub fn builder() -> ::Result<ClientBuilder> {
+    pub fn builder() -> ClientBuilder {
         ClientBuilder::new()
     }
 
@@ -239,7 +254,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn get<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn get<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Get, url)
     }
 
@@ -248,7 +263,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn post<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn post<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Post, url)
     }
 
@@ -257,7 +272,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn put<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn put<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Put, url)
     }
 
@@ -266,7 +281,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn patch<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn patch<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Patch, url)
     }
 
@@ -275,7 +290,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn delete<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn delete<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Delete, url)
     }
 
@@ -284,7 +299,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn head<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn head<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Head, url)
     }
 
@@ -296,9 +311,12 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn request<U: IntoUrl>(&self, method: Method, url: U) -> ::Result<RequestBuilder> {
-        let url = try_!(url.into_url());
-        Ok(request::builder(self.clone(), Request::new(method, url)))
+    pub fn request<U: IntoUrl>(&self, method: Method, url: U) -> RequestBuilder {
+        let req = match url.into_url() {
+            Ok(url) => Ok(Request::new(method, url)),
+            Err(err) => Err(::error::from(err)),
+        };
+        request::builder(self.clone(), req)
     }
 
     /// Executes a `Request`.
@@ -357,16 +375,18 @@ impl Client {
         let in_flight = self.inner.hyper.request(req);
 
         Pending {
-            method: method,
-            url: url,
-            headers: headers,
-            body: body,
+            inner: PendingInner::Request(PendingRequest {
+                method: method,
+                url: url,
+                headers: headers,
+                body: body,
 
-            urls: Vec::new(),
+                urls: Vec::new(),
 
-            client: self.inner.clone(),
+                client: self.inner.clone(),
 
-            in_flight: in_flight,
+                in_flight: in_flight,
+            }),
         }
     }
 }
@@ -397,6 +417,15 @@ struct ClientRef {
 }
 
 pub struct Pending {
+    inner: PendingInner,
+}
+
+enum PendingInner {
+    Request(PendingRequest),
+    Error(Option<::Error>),
+}
+
+pub struct PendingRequest {
     method: Method,
     url: Url,
     headers: Headers,
@@ -409,10 +438,23 @@ pub struct Pending {
     in_flight: FutureResponse,
 }
 
+
 impl Future for Pending {
     type Item = Response;
     type Error = ::Error;
 
+    fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
+        match self.inner {
+            PendingInner::Request(ref mut req) => req.poll(),
+            PendingInner::Error(ref mut err) => Err(err.take().expect("Pending error polled more than once")),
+        }
+    }
+}
+
+impl Future for PendingRequest {
+    type Item = Response;
+    type Error = ::Error;
+
     fn poll(&mut self) -> Poll<Self::Item, Self::Error> {
         loop {
             let res = match try_!(self.in_flight.poll(), &self.url) {
@@ -497,10 +539,19 @@ impl Future for Pending {
 
 impl fmt::Debug for Pending {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
-        f.debug_struct("Pending")
-            .field("method", &self.method)
-            .field("url", &self.url)
-            .finish()
+        match self.inner {
+            PendingInner::Request(ref req) => {
+                f.debug_struct("Pending")
+                    .field("method", &req.method)
+                    .field("url", &req.url)
+                    .finish()
+            },
+            PendingInner::Error(ref err) => {
+                f.debug_struct("Pending")
+                    .field("error", err)
+                    .finish()
+            }
+        }
     }
 }
 
@@ -520,5 +571,11 @@ fn make_referer(next: &Url, previous: &Url) -> Option<Referer> {
 
 pub fn take_builder(builder: &mut ClientBuilder) -> ClientBuilder {
     use std::mem;
-    mem::replace(builder, ClientBuilder { config: None })
+    mem::replace(builder, ClientBuilder { config: None, err: None })
+}
+
+pub fn pending_err(err: ::Error) -> Pending {
+    Pending {
+        inner: PendingInner::Error(Some(err)),
+    }
 }
diff --git a/src/async_impl/request.rs b/src/async_impl/request.rs
index ce53e0d00..74a91bbef 100644
--- a/src/async_impl/request.rs
+++ b/src/async_impl/request.rs
@@ -5,7 +5,7 @@ use serde_json;
 use serde_urlencoded;
 
 use super::body::{self, Body};
-use super::client::{Client, Pending};
+use super::client::{Client, Pending, pending_err};
 use header::{ContentType, Headers};
 use {Method, Url};
 
@@ -21,6 +21,7 @@ pub struct Request {
 pub struct RequestBuilder {
     client: Client,
     request: Option<Request>,
+    err: Option<::Error>,
 }
 
 impl Request {
@@ -90,14 +91,18 @@ impl RequestBuilder {
     where
         H: ::header::Header,
     {
-        self.request_mut().headers.set(header);
+        if let Some(req) = request_mut(&mut self.request, &self.err) {
+            req.headers_mut().set(header);
+        }
         self
     }
     /// Add a set of Headers to the existing ones on this Request.
     ///
     /// The headers will be merged in to any already set.
     pub fn headers(&mut self, headers: ::header::Headers) -> &mut RequestBuilder {
-        self.request_mut().headers.extend(headers.iter());
+        if let Some(req) = request_mut(&mut self.request, &self.err) {
+            req.headers_mut().extend(headers.iter());
+        }
         self
     }
 
@@ -115,20 +120,24 @@ impl RequestBuilder {
 
     /// Set the request body.
     pub fn body<T: Into<Body>>(&mut self, body: T) -> &mut RequestBuilder {
-        self.request_mut().body = Some(body.into());
+        if let Some(req) = request_mut(&mut self.request, &self.err) {
+            *req.body_mut() = Some(body.into());
+        }
         self
     }
 
     /// Send a form body.
-    pub fn form<T: Serialize>(&mut self, form: &T) -> ::Result<&mut RequestBuilder> {
-        {
-            // check request_mut() before running serde
-            let mut req = self.request_mut();
-            let body = try_!(serde_urlencoded::to_string(form));
-            req.headers.set(ContentType::form_url_encoded());
-            req.body = Some(body::reusable(body.into()));
+    pub fn form<T: Serialize>(&mut self, form: &T) -> &mut RequestBuilder {
+        if let Some(req) = request_mut(&mut self.request, &self.err) {
+            match serde_urlencoded::to_string(form) {
+                Ok(body) => {
+                    req.headers_mut().set(ContentType::form_url_encoded());
+                    *req.body_mut() = Some(body.into());
+                },
+                Err(err) => self.err = Some(::error::from(err)),
+            }
         }
-        Ok(self)
+        self
     }
 
     /// Send a JSON body.
@@ -137,15 +146,17 @@ impl RequestBuilder {
     ///
     /// Serialization can fail if `T`'s implementation of `Serialize` decides to
     /// fail, or if `T` contains a map with non-string keys.
-    pub fn json<T: Serialize>(&mut self, json: &T) -> ::Result<&mut RequestBuilder> {
-        {
-            // check request_mut() before running serde
-            let mut req = self.request_mut();
-            let body = try_!(serde_json::to_vec(json));
-            req.headers.set(ContentType::json());
-            req.body = Some(body::reusable(body.into()));
+    pub fn json<T: Serialize>(&mut self, json: &T) -> &mut RequestBuilder {
+        if let Some(req) = request_mut(&mut self.request, &self.err) {
+            match serde_json::to_vec(json) {
+                Ok(body) => {
+                    req.headers_mut().set(ContentType::json());
+                    *req.body_mut() = Some(body.into());
+                },
+                Err(err) => self.err = Some(::error::from(err)),
+            }
         }
-        Ok(self)
+        self
     }
 
     /// Build a `Request`, which can be inspected, modified and executed with
@@ -155,10 +166,14 @@ impl RequestBuilder {
     ///
     /// This method consumes builder internal state. It panics on an attempt to
     /// reuse already consumed builder.
-    pub fn build(&mut self) -> Request {
-        self.request
-            .take()
-            .expect("RequestBuilder cannot be reused after builder a Request")
+    pub fn build(&mut self) -> ::Result<Request> {
+        if let Some(err) = self.err.take() {
+            Err(err)
+        } else {
+            Ok(self.request
+                .take()
+                .expect("RequestBuilder cannot be reused after builder a Request"))
+        }
     }
 
     /// Constructs the Request and sends it the target URL, returning a Response.
@@ -168,16 +183,18 @@ impl RequestBuilder {
     /// This method fails if there was an error while sending request,
     /// redirect loop was detected or redirect limit was exhausted.
     pub fn send(&mut self) -> Pending {
-        let request = self.build();
-        self.client.execute(request)
+        match self.build() {
+            Ok(req) => self.client.execute(req),
+            Err(err) => pending_err(err),
+        }
     }
+}
 
-    // private
-
-    fn request_mut(&mut self) -> &mut Request {
-        self.request
-            .as_mut()
-            .expect("RequestBuilder cannot be reused after builder a Request")
+fn request_mut<'a>(req: &'a mut Option<Request>, err: &Option<::Error>) -> Option<&'a mut Request> {
+    if err.is_some() {
+        None
+    } else {
+        req.as_mut()
     }
 }
 
@@ -210,10 +227,18 @@ fn fmt_request_fields<'a, 'b>(f: &'a mut fmt::DebugStruct<'a, 'b>, req: &Request
 // pub(crate)
 
 #[inline]
-pub fn builder(client: Client, req: Request) -> RequestBuilder {
-    RequestBuilder {
-        client: client,
-        request: Some(req),
+pub fn builder(client: Client, req: ::Result<Request>) -> RequestBuilder {
+    match req {
+        Ok(req) => RequestBuilder {
+            client: client,
+            request: Some(req),
+            err: None,
+        },
+        Err(err) => RequestBuilder {
+            client: client,
+            request: None,
+            err: Some(err)
+        },
     }
 }
 
diff --git a/src/client.rs b/src/client.rs
index d27174d94..480c8d7e6 100644
--- a/src/client.rs
+++ b/src/client.rs
@@ -16,7 +16,7 @@ use {async_impl, Certificate, Identity, Method, IntoUrl, Proxy, RedirectPolicy,
 /// are set to what is usually the most commonly desired value.
 ///
 /// The `Client` holds a connection pool internally, so it is advised that
-/// you create one and reuse it.
+/// you create one and **reuse** it.
 ///
 /// # Examples
 ///
@@ -24,8 +24,8 @@ use {async_impl, Certificate, Identity, Method, IntoUrl, Proxy, RedirectPolicy,
 /// # use reqwest::{Error, Client};
 /// #
 /// # fn run() -> Result<(), Error> {
-/// let client = Client::new()?;
-/// let resp = client.get("http://httpbin.org/")?.send()?;
+/// let client = Client::new();
+/// let resp = client.get("http://httpbin.org/").send()?;
 /// #   drop(resp);
 /// #   Ok(())
 /// # }
@@ -44,7 +44,7 @@ pub struct Client {
 /// # fn run() -> Result<(), reqwest::Error> {
 /// use std::time::Duration;
 ///
-/// let client = reqwest::Client::builder()?
+/// let client = reqwest::Client::builder()
 ///     .gzip(true)
 ///     .timeout(Duration::from_secs(10))
 ///     .build()?;
@@ -58,15 +58,11 @@ pub struct ClientBuilder {
 
 impl ClientBuilder {
     /// Constructs a new `ClientBuilder`
-    ///
-    /// # Errors
-    ///
-    /// This method fails if native TLS backend cannot be created.
-    pub fn new() -> ::Result<ClientBuilder> {
-        async_impl::ClientBuilder::new().map(|builder| ClientBuilder {
-            inner: builder,
+    pub fn new() -> ClientBuilder {
+        ClientBuilder {
+            inner: async_impl::ClientBuilder::new(),
             timeout: Timeout::default(),
-        })
+        }
     }
 
     /// Returns a `Client` that uses this `ClientBuilder` configuration.
@@ -103,8 +99,8 @@ impl ClientBuilder {
     /// let cert = reqwest::Certificate::from_der(&buf)?;
     ///
     /// // get a client builder
-    /// let client = reqwest::ClientBuilder::new()?
-    ///     .add_root_certificate(cert)?
+    /// let client = reqwest::Client::builder()
+    ///     .add_root_certificate(cert)
     ///     .build()?;
     /// # drop(client);
     /// # Ok(())
@@ -114,17 +110,15 @@ impl ClientBuilder {
     /// # Errors
     ///
     /// This method fails if adding root certificate was unsuccessful.
-    pub fn add_root_certificate(&mut self, cert: Certificate) -> ::Result<&mut ClientBuilder> {
-        self.inner.add_root_certificate(cert)?;
-        Ok(self)
+    pub fn add_root_certificate(&mut self, cert: Certificate) -> &mut ClientBuilder {
+        self.inner.add_root_certificate(cert);
+        self
     }
 
     /// Sets the identity to be used for client certificate authentication.
     ///
-    /// This can be used in mutual authentication scenarios to identify to a server
-    /// with a PKCS#12 archive containing a certificate and private key for example.
-    ///
     /// # Example
+    ///
     /// ```
     /// # use std::fs::File;
     /// # use std::io::Read;
@@ -137,20 +131,16 @@ impl ClientBuilder {
     /// let pkcs12 = reqwest::Identity::from_pkcs12_der(&buf, "my-privkey-password")?;
     ///
     /// // get a client builder
-    /// let client = reqwest::ClientBuilder::new()?
-    ///     .identity(pkcs12)?
+    /// let client = reqwest::Client::builder()
+    ///     .identity(pkcs12)
     ///     .build()?;
     /// # drop(client);
     /// # Ok(())
     /// # }
     /// ```
-    ///
-    /// # Errors
-    ///
-    /// This method fails if adding client identity was unsuccessful.
-    pub fn identity(&mut self, identity: Identity) -> ::Result<&mut ClientBuilder> {
-        self.inner.identity(identity)?;
-        Ok(self)
+    pub fn identity(&mut self, identity: Identity) -> &mut ClientBuilder {
+        self.inner.identity(identity);
+        self
     }
 
 
@@ -229,21 +219,21 @@ impl ClientBuilder {
 impl Client {
     /// Constructs a new `Client`.
     ///
-    /// # Errors
+    /// # Panic
     ///
-    /// This method fails if native TLS backend cannot be created or initialized.
+    /// This method panics if native TLS backend cannot be created or
+    /// initialized. Use `Client::builder()` if you wish to handle the failure
+    /// as an `Error` instead of panicking.
     #[inline]
-    pub fn new() -> ::Result<Client> {
-        ClientBuilder::new()?.build()
+    pub fn new() -> Client {
+        ClientBuilder::new()
+            .build()
+            .expect("Client failed to initialize")
     }
 
     /// Creates a `ClientBuilder` to configure a `Client`.
-    ///
-    /// # Errors
-    ///
-    /// This method fails if native TLS backend cannot be created.
     #[inline]
-    pub fn builder() -> ::Result<ClientBuilder> {
+    pub fn builder() -> ClientBuilder {
         ClientBuilder::new()
     }
 
@@ -252,7 +242,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn get<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn get<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Get, url)
     }
 
@@ -261,7 +251,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn post<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn post<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Post, url)
     }
 
@@ -270,7 +260,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn put<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn put<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Put, url)
     }
 
@@ -279,7 +269,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn patch<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn patch<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Patch, url)
     }
 
@@ -288,7 +278,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn delete<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn delete<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Delete, url)
     }
 
@@ -297,7 +287,7 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn head<U: IntoUrl>(&self, url: U) -> ::Result<RequestBuilder> {
+    pub fn head<U: IntoUrl>(&self, url: U) -> RequestBuilder {
         self.request(Method::Head, url)
     }
 
@@ -309,9 +299,12 @@ impl Client {
     /// # Errors
     ///
     /// This method fails whenever supplied `Url` cannot be parsed.
-    pub fn request<U: IntoUrl>(&self, method: Method, url: U) -> ::Result<RequestBuilder> {
-        let url = try_!(url.into_url());
-        Ok(request::builder(self.clone(), Request::new(method, url)))
+    pub fn request<U: IntoUrl>(&self, method: Method, url: U) -> RequestBuilder {
+        let req = match url.into_url() {
+            Ok(url) => Ok(Request::new(method, url)),
+            Err(err) => Err(::error::from(err)),
+        };
+        request::builder(self.clone(), req)
     }
 
     /// Executes a `Request`.
diff --git a/src/lib.rs b/src/lib.rs
index 892bd3f1f..30601289b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -58,8 +58,8 @@
 //! # use reqwest::Error;
 //! #
 //! # fn run() -> Result<(), Error> {
-//! let client = reqwest::Client::new()?;
-//! let res = client.post("http://httpbin.org/post")?
+//! let client = reqwest::Client::new();
+//! let res = client.post("http://httpbin.org/post")
 //!     .body("the exact body that is sent")
 //!     .send()?;
 //! # Ok(())
@@ -80,9 +80,9 @@
 //! # fn run() -> Result<(), Error> {
 //! // This will POST a body of `foo=bar&baz=quux`
 //! let params = [("foo", "bar"), ("baz", "quux")];
-//! let client = reqwest::Client::new()?;
-//! let res = client.post("http://httpbin.org/post")?
-//!     .form(&params)?
+//! let client = reqwest::Client::new();
+//! let res = client.post("http://httpbin.org/post")
+//!     .form(&params)
 //!     .send()?;
 //! # Ok(())
 //! # }
@@ -104,9 +104,9 @@
 //! map.insert("lang", "rust");
 //! map.insert("body", "json");
 //!
-//! let client = reqwest::Client::new()?;
-//! let res = client.post("http://httpbin.org/post")?
-//!     .json(&map)?
+//! let client = reqwest::Client::new();
+//! let res = client.post("http://httpbin.org/post")
+//!     .json(&map)
 //!     .send()?;
 //! # Ok(())
 //! # }
@@ -228,8 +228,8 @@ pub mod unstable {
 /// - redirect loop was detected
 /// - redirect limit was exhausted
 pub fn get<T: IntoUrl>(url: T) -> ::Result<Response> {
-    Client::new()?
-        .get(url)?
+    Client::new()
+        .get(url)
         .send()
 }
 
diff --git a/src/proxy.rs b/src/proxy.rs
index 3d74661d6..65b8d4371 100644
--- a/src/proxy.rs
+++ b/src/proxy.rs
@@ -43,7 +43,7 @@ impl Proxy {
     /// ```
     /// # extern crate reqwest;
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
-    /// let client = reqwest::Client::builder()?
+    /// let client = reqwest::Client::builder()
     ///     .proxy(reqwest::Proxy::http("https://my.prox")?)
     ///     .build()?;
     /// # Ok(())
@@ -62,7 +62,7 @@ impl Proxy {
     /// ```
     /// # extern crate reqwest;
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
-    /// let client = reqwest::Client::builder()?
+    /// let client = reqwest::Client::builder()
     ///     .proxy(reqwest::Proxy::https("https://example.prox:4545")?)
     ///     .build()?;
     /// # Ok(())
@@ -81,7 +81,7 @@ impl Proxy {
     /// ```
     /// # extern crate reqwest;
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
-    /// let client = reqwest::Client::builder()?
+    /// let client = reqwest::Client::builder()
     ///     .proxy(reqwest::Proxy::all("http://pro.xy")?)
     ///     .build()?;
     /// # Ok(())
@@ -101,7 +101,7 @@ impl Proxy {
     /// # extern crate reqwest;
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
     /// let target = reqwest::Url::parse("https://my.prox")?;
-    /// let client = reqwest::Client::builder()?
+    /// let client = reqwest::Client::builder()
     ///     .proxy(reqwest::Proxy::custom(move |url| {
     ///         if url.host_str() == Some("hyper.rs") {
     ///             Some(target.clone())
diff --git a/src/redirect.rs b/src/redirect.rs
index c6c3b0da9..273ff04e4 100644
--- a/src/redirect.rs
+++ b/src/redirect.rs
@@ -74,7 +74,7 @@ impl RedirectPolicy {
     ///         attempt.follow()
     ///     }
     /// });
-    /// let client = reqwest::Client::builder()?
+    /// let client = reqwest::Client::builder()
     ///     .redirect(custom)
     ///     .build()?;
     /// # Ok(())
diff --git a/src/request.rs b/src/request.rs
index 0e7d6512a..6a43be5f0 100644
--- a/src/request.rs
+++ b/src/request.rs
@@ -19,6 +19,7 @@ pub struct Request {
 pub struct RequestBuilder {
     client: Client,
     request: Option<Request>,
+    err: Option<::Error>,
 }
 
 impl Request {
@@ -87,8 +88,8 @@ impl RequestBuilder {
     /// use reqwest::header::UserAgent;
     ///
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
-    /// let client = reqwest::Client::new()?;
-    /// let res = client.get("https://www.rust-lang.org")?
+    /// let client = reqwest::Client::new();
+    /// let res = client.get("https://www.rust-lang.org")
     ///     .header(UserAgent::new("foo"))
     ///     .send()?;
     /// # Ok(())
@@ -98,7 +99,9 @@ impl RequestBuilder {
     where
         H: ::header::Header,
     {
-        self.request_mut().headers_mut().set(header);
+        if let Some(req) = request_mut(&mut self.request, &self.err) {
+            req.headers_mut().set(header);
+        }
         self
     }
 
@@ -119,8 +122,8 @@ impl RequestBuilder {
     ///
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
     /// let file = fs::File::open("much_beauty.png")?;
-    /// let client = reqwest::Client::new()?;
-    /// let res = client.post("http://httpbin.org/post")?
+    /// let client = reqwest::Client::new();
+    /// let res = client.post("http://httpbin.org/post")
     ///     .headers(construct_headers())
     ///     .body(file)
     ///     .send()?;
@@ -128,7 +131,9 @@ impl RequestBuilder {
     /// # }
     /// ```
     pub fn headers(&mut self, headers: ::header::Headers) -> &mut RequestBuilder {
-        self.request_mut().headers_mut().extend(headers.iter());
+        if let Some(req) = request_mut(&mut self.request, &self.err) {
+            req.headers_mut().extend(headers.iter());
+        }
         self
     }
 
@@ -136,8 +141,8 @@ impl RequestBuilder {
     ///
     /// ```rust
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
-    /// let client = reqwest::Client::new()?;
-    /// let resp = client.delete("http://httpbin.org/delete")?
+    /// let client = reqwest::Client::new();
+    /// let resp = client.delete("http://httpbin.org/delete")
     ///     .basic_auth("admin", Some("good password"))
     ///     .send()?;
     /// # Ok(())
@@ -162,8 +167,8 @@ impl RequestBuilder {
     ///
     /// ```rust
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
-    /// let client = reqwest::Client::new()?;
-    /// let res = client.post("http://httpbin.org/post")?
+    /// let client = reqwest::Client::new();
+    /// let res = client.post("http://httpbin.org/post")
     ///     .body("from a &str!")
     ///     .send()?;
     /// # Ok(())
@@ -176,8 +181,8 @@ impl RequestBuilder {
     /// # use std::fs;
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
     /// let file = fs::File::open("from_a_file.txt")?;
-    /// let client = reqwest::Client::new()?;
-    /// let res = client.post("http://httpbin.org/post")?
+    /// let client = reqwest::Client::new();
+    /// let res = client.post("http://httpbin.org/post")
     ///     .body(file)
     ///     .send()?;
     /// # Ok(())
@@ -191,15 +196,17 @@ impl RequestBuilder {
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
     /// // from bytes!
     /// let bytes: Vec<u8> = vec![1, 10, 100];
-    /// let client = reqwest::Client::new()?;
-    /// let res = client.post("http://httpbin.org/post")?
+    /// let client = reqwest::Client::new();
+    /// let res = client.post("http://httpbin.org/post")
     ///     .body(bytes)
     ///     .send()?;
     /// # Ok(())
     /// # }
     /// ```
     pub fn body<T: Into<Body>>(&mut self, body: T) -> &mut RequestBuilder {
-        *self.request_mut().body_mut() = Some(body.into());
+        if let Some(req) = request_mut(&mut self.request, &self.err) {
+            *req.body_mut() = Some(body.into());
+        }
         self
     }
 
@@ -217,9 +224,9 @@ impl RequestBuilder {
     /// let mut params = HashMap::new();
     /// params.insert("lang", "rust");
     ///
-    /// let client = reqwest::Client::new()?;
-    /// let res = client.post("http://httpbin.org")?
-    ///     .form(&params)?
+    /// let client = reqwest::Client::new();
+    /// let res = client.post("http://httpbin.org")
+    ///     .form(&params)
     ///     .send()?;
     /// # Ok(())
     /// # }
@@ -229,16 +236,17 @@ impl RequestBuilder {
     ///
     /// This method fails if the passed value cannot be serialized into
     /// url encoded format
-    pub fn form<T: Serialize>(&mut self, form: &T) -> ::Result<&mut RequestBuilder> {
-
-        {
-            // check request_mut() before running serde
-            let req = self.request_mut();
-            let body = try_!(serde_urlencoded::to_string(form));
-            req.headers_mut().set(ContentType::form_url_encoded());
-            *req.body_mut() = Some(body.into());
+    pub fn form<T: Serialize>(&mut self, form: &T) -> &mut RequestBuilder {
+        if let Some(req) = request_mut(&mut self.request, &self.err) {
+            match serde_urlencoded::to_string(form) {
+                Ok(body) => {
+                    req.headers_mut().set(ContentType::form_url_encoded());
+                    *req.body_mut() = Some(body.into());
+                },
+                Err(err) => self.err = Some(::error::from(err)),
+            }
         }
-        Ok(self)
+        self
     }
 
     /// Send a JSON body.
@@ -254,9 +262,9 @@ impl RequestBuilder {
     /// let mut map = HashMap::new();
     /// map.insert("lang", "rust");
     ///
-    /// let client = reqwest::Client::new()?;
-    /// let res = client.post("http://httpbin.org")?
-    ///     .json(&map)?
+    /// let client = reqwest::Client::new();
+    /// let res = client.post("http://httpbin.org")
+    ///     .json(&map)
     ///     .send()?;
     /// # Ok(())
     /// # }
@@ -266,15 +274,17 @@ impl RequestBuilder {
     ///
     /// Serialization can fail if `T`'s implementation of `Serialize` decides to
     /// fail, or if `T` contains a map with non-string keys.
-    pub fn json<T: Serialize>(&mut self, json: &T) -> ::Result<&mut RequestBuilder> {
-        {
-            // check request_mut() before running serde
-            let req = self.request_mut();
-            let body = try_!(serde_json::to_vec(json));
-            req.headers_mut().set(ContentType::json());
-            *req.body_mut() = Some(body.into());
+    pub fn json<T: Serialize>(&mut self, json: &T) -> &mut RequestBuilder {
+        if let Some(req) = request_mut(&mut self.request, &self.err) {
+            match serde_json::to_vec(json) {
+                Ok(body) => {
+                    req.headers_mut().set(ContentType::json());
+                    *req.body_mut() = Some(body.into());
+                },
+                Err(err) => self.err = Some(::error::from(err)),
+            }
         }
-        Ok(self)
+        self
     }
 
     /// Sends a multipart/form-data body.
@@ -284,12 +294,12 @@ impl RequestBuilder {
     /// # use reqwest::Error;
     ///
     /// # fn run() -> Result<(), Box<std::error::Error>> {
-    /// let client = reqwest::Client::new()?;
+    /// let client = reqwest::Client::new();
     /// let form = reqwest::multipart::Form::new()
     ///     .text("key3", "value3")
     ///     .file("file", "/path/to/field")?;
     ///
-    /// let response = client.post("your url")?
+    /// let response = client.post("your url")
     ///     .multipart(form)
     ///     .send()?;
     /// # Ok(())
@@ -298,8 +308,7 @@ impl RequestBuilder {
     ///
     /// See [`multipart`](multipart/) for more examples.
     pub fn multipart(&mut self, mut multipart: ::multipart::Form) -> &mut RequestBuilder {
-        {
-            let req = self.request_mut();
+        if let Some(req) = request_mut(&mut self.request, &self.err) {
             req.headers_mut().set(
                 ::header::ContentType(format!("multipart/form-data; boundary={}", ::multipart_::boundary(&multipart))
                     .parse().unwrap()
@@ -320,10 +329,14 @@ impl RequestBuilder {
     ///
     /// This method consumes builder internal state. It panics on an attempt to
     /// reuse already consumed builder.
-    pub fn build(&mut self) -> Request {
-        self.request
-            .take()
-            .expect("RequestBuilder cannot be reused after builder a Request")
+    pub fn build(&mut self) -> ::Result<Request> {
+        if let Some(err) = self.err.take() {
+            Err(err)
+        } else {
+            Ok(self.request
+                .take()
+                .expect("RequestBuilder cannot be reused after builder a Request"))
+        }
     }
 
     /// Constructs the Request and sends it the target URL, returning a Response.
@@ -333,16 +346,18 @@ impl RequestBuilder {
     /// This method fails if there was an error while sending request,
     /// redirect loop was detected or redirect limit was exhausted.
     pub fn send(&mut self) -> ::Result<::Response> {
-        let request = self.build();
+        let request = self.build()?;
         self.client.execute(request)
     }
 
-    // private
+}
+
 
-    fn request_mut(&mut self) -> &mut Request {
-        self.request
-            .as_mut()
-            .expect("RequestBuilder cannot be reused after builder a Request")
+fn request_mut<'a>(req: &'a mut Option<Request>, err: &Option<::Error>) -> Option<&'a mut Request> {
+    if err.is_some() {
+        None
+    } else {
+        req.as_mut()
     }
 }
 
@@ -375,10 +390,18 @@ fn fmt_request_fields<'a, 'b>(f: &'a mut fmt::DebugStruct<'a, 'b>, req: &Request
 // pub(crate)
 
 #[inline]
-pub fn builder(client: Client, req: Request) -> RequestBuilder {
-    RequestBuilder {
-        client: client,
-        request: Some(req),
+pub fn builder(client: Client, req: ::Result<Request>) -> RequestBuilder {
+    match req {
+        Ok(req) => RequestBuilder {
+            client: client,
+            request: Some(req),
+            err: None,
+        },
+        Err(err) => RequestBuilder {
+            client: client,
+            request: None,
+            err: Some(err)
+        },
     }
 }
 
@@ -408,9 +431,9 @@ mod tests {
 
     #[test]
     fn basic_get_request() {
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let r = client.get(some_url).unwrap().build();
+        let r = client.get(some_url).build().unwrap();
 
         assert_eq!(r.method(), &Method::Get);
         assert_eq!(r.url().as_str(), some_url);
@@ -418,9 +441,9 @@ mod tests {
 
     #[test]
     fn basic_head_request() {
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let r = client.head(some_url).unwrap().build();
+        let r = client.head(some_url).build().unwrap();
 
         assert_eq!(r.method(), &Method::Head);
         assert_eq!(r.url().as_str(), some_url);
@@ -428,9 +451,9 @@ mod tests {
 
     #[test]
     fn basic_post_request() {
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let r = client.post(some_url).unwrap().build();
+        let r = client.post(some_url).build().unwrap();
 
         assert_eq!(r.method(), &Method::Post);
         assert_eq!(r.url().as_str(), some_url);
@@ -438,9 +461,9 @@ mod tests {
 
     #[test]
     fn basic_put_request() {
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let r = client.put(some_url).unwrap().build();
+        let r = client.put(some_url).build().unwrap();
 
         assert_eq!(r.method(), &Method::Put);
         assert_eq!(r.url().as_str(), some_url);
@@ -448,9 +471,9 @@ mod tests {
 
     #[test]
     fn basic_patch_request() {
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let r = client.patch(some_url).unwrap().build();
+        let r = client.patch(some_url).build().unwrap();
 
         assert_eq!(r.method(), &Method::Patch);
         assert_eq!(r.url().as_str(), some_url);
@@ -458,9 +481,9 @@ mod tests {
 
     #[test]
     fn basic_delete_request() {
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let r = client.delete(some_url).unwrap().build();
+        let r = client.delete(some_url).build().unwrap();
 
         assert_eq!(r.method(), &Method::Delete);
         assert_eq!(r.url().as_str(), some_url);
@@ -468,14 +491,14 @@ mod tests {
 
     #[test]
     fn add_header() {
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let mut r = client.post(some_url).unwrap();
+        let mut r = client.post(some_url);
 
         let header = Host::new("google.com", None);
 
         // Add a copy of the header to the request builder
-        let r = r.header(header.clone()).build();
+        let r = r.header(header.clone()).build().unwrap();
 
         // then check it was actually added
         assert_eq!(r.headers().get::<Host>(), Some(&header));
@@ -483,9 +506,9 @@ mod tests {
 
     #[test]
     fn add_headers() {
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let mut r = client.post(some_url).unwrap();
+        let mut r = client.post(some_url);
 
         let header = Host::new("google.com", None);
 
@@ -493,7 +516,7 @@ mod tests {
         headers.set(header);
 
         // Add a copy of the headers to the request builder
-        let r = r.headers(headers.clone()).build();
+        let r = r.headers(headers.clone()).build().unwrap();
 
         // then make sure they were added correctly
         assert_eq!(r.headers(), &headers);
@@ -501,13 +524,13 @@ mod tests {
 
     #[test]
     fn add_body() {
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let mut r = client.post(some_url).unwrap();
+        let mut r = client.post(some_url);
 
         let body = "Some interesting content";
 
-        let mut r = r.body(body).build();
+        let mut r = r.body(body).build().unwrap();
 
         let buf = body::read_to_string(r.body_mut().take().unwrap()).unwrap();
 
@@ -516,14 +539,14 @@ mod tests {
 
     #[test]
     fn add_form() {
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let mut r = client.post(some_url).unwrap();
+        let mut r = client.post(some_url);
 
         let mut form_data = HashMap::new();
         form_data.insert("foo", "bar");
 
-        let mut r = r.form(&form_data).unwrap().build();
+        let mut r = r.form(&form_data).build().unwrap();
 
         // Make sure the content type was set
         assert_eq!(r.headers().get::<ContentType>(),
@@ -537,14 +560,14 @@ mod tests {
 
     #[test]
     fn add_json() {
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let mut r = client.post(some_url).unwrap();
+        let mut r = client.post(some_url);
 
         let mut json_data = HashMap::new();
         json_data.insert("foo", "bar");
 
-        let mut r = r.json(&json_data).unwrap().build();
+        let mut r = r.json(&json_data).build().unwrap();
 
         // Make sure the content type was set
         assert_eq!(r.headers().get::<ContentType>(), Some(&ContentType::json()));
@@ -568,10 +591,10 @@ mod tests {
                 }
         }
 
-        let client = Client::new().unwrap();
+        let client = Client::new();
         let some_url = "https://google.com/";
-        let mut r = client.post(some_url).unwrap();
+        let mut r = client.post(some_url);
         let json_data = MyStruct;
-        assert!(r.json(&json_data).unwrap_err().is_serialization());
+        assert!(r.json(&json_data).build().unwrap_err().is_serialization());
     }
 }
diff --git a/src/response.rs b/src/response.rs
index 86d588c76..61394d415 100644
--- a/src/response.rs
+++ b/src/response.rs
@@ -63,8 +63,8 @@ impl Response {
     /// use reqwest::Client;
     /// use reqwest::StatusCode;
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
-    /// let client = Client::new()?;
-    /// let resp = client.post("http://httpbin.org/post")?
+    /// let client = Client::new();
+    /// let resp = client.post("http://httpbin.org/post")
     ///             .body("possibly too large")
     ///             .send()?;
     /// match resp.status() {
@@ -94,8 +94,8 @@ impl Response {
     /// # use reqwest::header::ContentLength;
     /// #
     /// # fn run() -> Result<(), Box<::std::error::Error>> {
-    /// let client = Client::new()?;
-    /// let mut resp = client.head("http://httpbin.org/bytes/3000")?.send()?;
+    /// let client = Client::new();
+    /// let mut resp = client.head("http://httpbin.org/bytes/3000").send()?;
     /// if resp.status().is_success() {
     ///     let len = resp.headers().get::<ContentLength>()
     ///                 .map(|ct_len| **ct_len)


Test patch:
diff --git a/tests/async.rs b/tests/async.rs
index 6a556ef00..0f0078906 100644
--- a/tests/async.rs
+++ b/tests/async.rs
@@ -61,10 +61,9 @@ fn test_gzip(response_size: usize, chunk_size: usize) {
 
     let mut core = Core::new().unwrap();
 
-    let client = Client::new(&core.handle()).unwrap();
+    let client = Client::new(&core.handle());
 
     let res_future = client.get(&format!("http://{}/gzip", server.addr()))
-        .unwrap()
         .send()
         .and_then(|mut res| {
             let body = mem::replace(res.body_mut(), Decoder::empty());
diff --git a/tests/client.rs b/tests/client.rs
index 979c29a3d..bd4f6a8a9 100644
--- a/tests/client.rs
+++ b/tests/client.rs
@@ -62,9 +62,7 @@ fn test_post() {
 
     let url = format!("http://{}/2", server.addr());
     let mut res = reqwest::Client::new()
-        .unwrap()
         .post(&url)
-        .unwrap()
         .body("Hello")
         .send()
         .unwrap();
diff --git a/tests/gzip.rs b/tests/gzip.rs
index e720eefaf..15715c342 100644
--- a/tests/gzip.rs
+++ b/tests/gzip.rs
@@ -68,10 +68,9 @@ fn test_gzip_empty_body() {
             \r\n"
     };
 
-    let client = reqwest::Client::new().unwrap();
+    let client = reqwest::Client::new();
     let mut res = client
         .head(&format!("http://{}/gzip", server.addr()))
-        .unwrap()
         .send()
         .unwrap();
 
@@ -127,11 +126,10 @@ fn test_accept_header_is_not_changed_if_set() {
             \r\n\
             "
     };
-    let client = reqwest::Client::new().unwrap();
+    let client = reqwest::Client::new();
 
     let res = client
         .get(&format!("http://{}/accept", server.addr()))
-        .unwrap()
         .header(reqwest::header::Accept::json())
         .send()
         .unwrap();
@@ -157,10 +155,9 @@ fn test_accept_encoding_header_is_not_changed_if_set() {
             \r\n\
             "
     };
-    let client = reqwest::Client::new().unwrap();
+    let client = reqwest::Client::new();
 
     let res = client.get(&format!("http://{}/accept-encoding", server.addr()))
-        .unwrap()
         .header(reqwest::header::AcceptEncoding(
             vec![reqwest::header::qitem(reqwest::header::Encoding::Identity)]
         ))
diff --git a/tests/multipart.rs b/tests/multipart.rs
index 6f53d031c..e832b33a5 100644
--- a/tests/multipart.rs
+++ b/tests/multipart.rs
@@ -38,9 +38,7 @@ fn test_multipart() {
     let url = format!("http://{}/multipart/1", server.addr());
 
     let res = reqwest::Client::new()
-        .unwrap()
         .post(&url)
-        .unwrap()
         .multipart(form)
         .send()
         .unwrap();
diff --git a/tests/proxy.rs b/tests/proxy.rs
index c75acfafc..75dbbb692 100644
--- a/tests/proxy.rs
+++ b/tests/proxy.rs
@@ -26,12 +26,10 @@ fn test_http_proxy() {
 
     let url = "http://hyper.rs/prox";
     let res = reqwest::Client::builder()
-        .unwrap()
         .proxy(reqwest::Proxy::http(&proxy).unwrap())
         .build()
         .unwrap()
         .get(url)
-        .unwrap()
         .send()
         .unwrap();
 
diff --git a/tests/redirect.rs b/tests/redirect.rs
index 2c2244caa..ff46d5a7f 100644
--- a/tests/redirect.rs
+++ b/tests/redirect.rs
@@ -5,7 +5,7 @@ mod support;
 
 #[test]
 fn test_redirect_301_and_302_and_303_changes_post_to_get() {
-    let client = reqwest::Client::new().unwrap();
+    let client = reqwest::Client::new();
     let codes = [301, 302, 303];
 
     for code in codes.iter() {
@@ -47,7 +47,6 @@ fn test_redirect_301_and_302_and_303_changes_post_to_get() {
         let url = format!("http://{}/{}", redirect.addr(), code);
         let dst = format!("http://{}/{}", redirect.addr(), "dst");
         let res = client.post(&url)
-            .unwrap()
             .send()
             .unwrap();
         assert_eq!(res.url().as_str(), dst);
@@ -59,7 +58,7 @@ fn test_redirect_301_and_302_and_303_changes_post_to_get() {
 
 #[test]
 fn test_redirect_307_and_308_tries_to_get_again() {
-    let client = reqwest::Client::new().unwrap();
+    let client = reqwest::Client::new();
     let codes = [307, 308];
     for code in codes.iter() {
         let redirect = server! {
@@ -100,7 +99,6 @@ fn test_redirect_307_and_308_tries_to_get_again() {
         let url = format!("http://{}/{}", redirect.addr(), code);
         let dst = format!("http://{}/{}", redirect.addr(), "dst");
         let res = client.get(&url)
-            .unwrap()
             .send()
             .unwrap();
         assert_eq!(res.url().as_str(), dst);
@@ -112,7 +110,7 @@ fn test_redirect_307_and_308_tries_to_get_again() {
 
 #[test]
 fn test_redirect_307_and_308_tries_to_post_again() {
-    let client = reqwest::Client::new().unwrap();
+    let client = reqwest::Client::new();
     let codes = [307, 308];
     for code in codes.iter() {
         let redirect = server! {
@@ -157,7 +155,6 @@ fn test_redirect_307_and_308_tries_to_post_again() {
         let url = format!("http://{}/{}", redirect.addr(), code);
         let dst = format!("http://{}/{}", redirect.addr(), "dst");
         let res = client.post(&url)
-            .unwrap()
             .body("Hello")
             .send()
             .unwrap();
@@ -170,7 +167,7 @@ fn test_redirect_307_and_308_tries_to_post_again() {
 
 #[test]
 fn test_redirect_307_does_not_try_if_reader_cannot_reset() {
-    let client = reqwest::Client::new().unwrap();
+    let client = reqwest::Client::new();
     let codes = [307, 308];
     for &code in codes.iter() {
         let redirect = server! {
@@ -199,7 +196,6 @@ fn test_redirect_307_does_not_try_if_reader_cannot_reset() {
         let url = format!("http://{}/{}", redirect.addr(), code);
         let res = client
             .post(&url)
-            .unwrap()
             .body(reqwest::Body::new(&b"Hello"[..]))
             .send()
             .unwrap();
@@ -251,12 +247,10 @@ fn test_redirect_removes_sensitive_headers() {
     let mut cookie = reqwest::header::Cookie::new();
     cookie.set("foo", "bar");
     reqwest::Client::builder()
-        .unwrap()
         .referer(false)
         .build()
         .unwrap()
         .get(&format!("http://{}/sensitive", mid_server.addr()))
-        .unwrap()
         .header(cookie)
         .send()
         .unwrap();
@@ -309,12 +303,10 @@ fn test_redirect_policy_can_stop_redirects_without_an_error() {
     let url = format!("http://{}/no-redirect", server.addr());
 
     let res = reqwest::Client::builder()
-        .unwrap()
         .redirect(reqwest::RedirectPolicy::none())
         .build()
         .unwrap()
         .get(&url)
-        .unwrap()
         .send()
         .unwrap();
 
@@ -359,12 +351,12 @@ fn test_referer_is_not_set_if_disabled() {
             \r\n\
             "
     };
-    reqwest::Client::builder().unwrap()
+    reqwest::Client::builder()
         .referer(false)
-        .build().unwrap()
+        .build()
+        .unwrap()
         //client
         .get(&format!("http://{}/no-refer", server.addr()))
-        .unwrap()
         .send()
         .unwrap();
 }
diff --git a/tests/timeouts.rs b/tests/timeouts.rs
index 6d0df4f4a..088f5f85e 100644
--- a/tests/timeouts.rs
+++ b/tests/timeouts.rs
@@ -30,12 +30,10 @@ fn test_write_timeout() {
 
     let url = format!("http://{}/write-timeout", server.addr());
     let err = reqwest::Client::builder()
-        .unwrap()
         .timeout(Duration::from_millis(500))
         .build()
         .unwrap()
         .post(&url)
-        .unwrap()
         .header(reqwest::header::ContentLength(5))
         .body(reqwest::Body::new(&b"Hello"[..]))
         .send()
@@ -66,12 +64,10 @@ fn test_response_timeout() {
 
     let url = format!("http://{}/response-timeout", server.addr());
     let err = reqwest::Client::builder()
-        .unwrap()
         .timeout(Duration::from_millis(500))
         .build()
         .unwrap()
         .get(&url)
-        .unwrap()
         .send()
         .unwrap_err();
 
@@ -101,12 +97,10 @@ fn test_read_timeout() {
 
     let url = format!("http://{}/read-timeout", server.addr());
     let mut res = reqwest::Client::builder()
-        .unwrap()
         .timeout(Duration::from_millis(500))
         .build()
         .unwrap()
         .get(&url)
-        .unwrap()
         .send()
         .unwrap();