-- Mathlib/CategoryTheory/Abelian/RightDerived.lean
@[reassoc]
lemma InjectiveResolution.isoRightDerivedObj_hom_naturality
    {X Y : C} (f : X ⟶ Y) (I : InjectiveResolution X) (J : InjectiveResolution Y)
    (φ : I.cocomplex ⟶ J.cocomplex) (comm : I.ι.f 0 ≫ φ.f 0 = f ≫ J.ι.f 0)
    (F : C ⥤ D) [F.Additive] (n : ℕ) :
    (F.rightDerived n).map f ≫ (J.isoRightDerivedObj F n).hom =
      (I.isoRightDerivedObj F n).hom ≫
        (F.mapHomologicalComplex _ ⋙ HomologicalComplex.homologyFunctor _ _ n).map φ

Proof state:
C : Type u
inst✝⁵ : Category.{v, u} C
D : Type u_1
inst✝⁴ : Category.{u_2, u_1} D
inst✝³ : Abelian C
inst✝² : HasInjectiveResolutions C
inst✝¹ : Abelian D
X Y : C
f : X ⟶ Y
I : InjectiveResolution X
J : InjectiveResolution Y
φ : I.cocomplex ⟶ J.cocomplex
comm : I.ι.f 0 ≫ φ.f 0 = f ≫ J.ι.f 0
F : C ⥤ D
inst✝ : F.Additive
n : ℕ
⊢ (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map (I.isoRightDerivedToHomotopyCategoryObj F).hom ≫
      (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map
          ((F.mapHomologicalComplex (ComplexShape.up ℕ) ⋙ HomotopyCategory.quotient D (ComplexShape.up ℕ)).map φ) ≫
        (HomotopyCategory.homologyFunctorFactors D (ComplexShape.up ℕ) n).hom.app
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).obj J.cocomplex) =
    (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map (I.isoRightDerivedToHomotopyCategoryObj F).hom ≫
      (HomotopyCategory.homologyFunctorFactors D (ComplexShape.up ℕ) n).hom.app
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).obj I.cocomplex) ≫
        HomologicalComplex.homologyMap ((F.mapHomologicalComplex (ComplexShape.up ℕ)).map φ) n

Tactic:
erw [(HomotopyCategory.homologyFunctorFactors D (ComplexShape.up ℕ) n).hom.naturality]

Result:
C : Type u
inst✝⁵ : Category.{v, u} C
D : Type u_1
inst✝⁴ : Category.{u_2, u_1} D
inst✝³ : Abelian C
inst✝² : HasInjectiveResolutions C
inst✝¹ : Abelian D
X Y : C
f : X ⟶ Y
I : InjectiveResolution X
J : InjectiveResolution Y
φ : I.cocomplex ⟶ J.cocomplex
comm : I.ι.f 0 ≫ φ.f 0 = f ≫ J.ι.f 0
F : C ⥤ D
inst✝ : F.Additive
n : ℕ
⊢ (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map (I.isoRightDerivedToHomotopyCategoryObj F).hom ≫
      (HomotopyCategory.homologyFunctorFactors D (ComplexShape.up ℕ) n).hom.app
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).obj I.cocomplex) ≫
        (HomologicalComplex.homologyFunctor D (ComplexShape.up ℕ) n).map
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).map φ) =
    (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map (I.isoRightDerivedToHomotopyCategoryObj F).hom ≫
      (HomotopyCategory.homologyFunctorFactors D (ComplexShape.up ℕ) n).hom.app
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).obj I.cocomplex) ≫
        HomologicalComplex.homologyMap ((F.mapHomologicalComplex (ComplexShape.up ℕ)).map φ) n

Proof state:
C : Type u
inst✝⁵ : Category.{v, u} C
D : Type u_1
inst✝⁴ : Category.{u_2, u_1} D
inst✝³ : Abelian C
inst✝² : HasInjectiveResolutions C
inst✝¹ : Abelian D
X Y : C
f : X ⟶ Y
I : InjectiveResolution X
J : InjectiveResolution Y
φ : I.cocomplex ⟶ J.cocomplex
comm : I.ι.f 0 ≫ φ.f 0 = f ≫ J.ι.f 0
F : C ⥤ D
inst✝ : F.Additive
n : ℕ
⊢ (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map (I.isoRightDerivedToHomotopyCategoryObj F).hom ≫
      (HomotopyCategory.homologyFunctorFactors D (ComplexShape.up ℕ) n).hom.app
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).obj I.cocomplex) ≫
        (HomologicalComplex.homologyFunctor D (ComplexShape.up ℕ) n).map
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).map φ) =
    (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map (I.isoRightDerivedToHomotopyCategoryObj F).hom ≫
      (HomotopyCategory.homologyFunctorFactors D (ComplexShape.up ℕ) n).hom.app
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).obj I.cocomplex) ≫
        HomologicalComplex.homologyMap ((F.mapHomologicalComplex (ComplexShape.up ℕ)).map φ) n

Tactic:
rfl

Result:
no goals

Proof state:
C : Type u
inst✝⁵ : Category.{v, u} C
D : Type u_1
inst✝⁴ : Category.{u_2, u_1} D
inst✝³ : Abelian C
inst✝² : HasInjectiveResolutions C
inst✝¹ : Abelian D
X Y : C
f : X ⟶ Y
I : InjectiveResolution X
J : InjectiveResolution Y
φ : I.cocomplex ⟶ J.cocomplex
comm : I.ι.f 0 ≫ φ.f 0 = f ≫ J.ι.f 0
F : C ⥤ D
inst✝ : F.Additive
n : ℕ
⊢ (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map (F.rightDerivedToHomotopyCategory.map f) ≫
      (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map (J.isoRightDerivedToHomotopyCategoryObj F).hom ≫
        (HomotopyCategory.homologyFunctorFactors D (ComplexShape.up ℕ) n).hom.app
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).obj J.cocomplex) =
    ((HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map (I.isoRightDerivedToHomotopyCategoryObj F).hom ≫
        (HomotopyCategory.homologyFunctorFactors D (ComplexShape.up ℕ) n).hom.app
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).obj I.cocomplex)) ≫
      HomologicalComplex.homologyMap ((F.mapHomologicalComplex (ComplexShape.up ℕ)).map φ) n

Tactic:
rw [assoc, ← Functor.map_comp_assoc,
  InjectiveResolution.isoRightDerivedToHomotopyCategoryObj_hom_naturality f I J φ comm F,
  Functor.map_comp, assoc]

Result:
C : Type u
inst✝⁵ : Category.{v, u} C
D : Type u_1
inst✝⁴ : Category.{u_2, u_1} D
inst✝³ : Abelian C
inst✝² : HasInjectiveResolutions C
inst✝¹ : Abelian D
X Y : C
f : X ⟶ Y
I : InjectiveResolution X
J : InjectiveResolution Y
φ : I.cocomplex ⟶ J.cocomplex
comm : I.ι.f 0 ≫ φ.f 0 = f ≫ J.ι.f 0
F : C ⥤ D
inst✝ : F.Additive
n : ℕ
⊢ (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map (I.isoRightDerivedToHomotopyCategoryObj F).hom ≫
      (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map
          ((F.mapHomologicalComplex (ComplexShape.up ℕ) ⋙ HomotopyCategory.quotient D (ComplexShape.up ℕ)).map φ) ≫
        (HomotopyCategory.homologyFunctorFactors D (ComplexShape.up ℕ) n).hom.app
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).obj J.cocomplex) =
    (HomotopyCategory.homologyFunctor D (ComplexShape.up ℕ) n).map (I.isoRightDerivedToHomotopyCategoryObj F).hom ≫
      (HomotopyCategory.homologyFunctorFactors D (ComplexShape.up ℕ) n).hom.app
          ((F.mapHomologicalComplex (ComplexShape.up ℕ)).obj I.cocomplex) ≫
        HomologicalComplex.homologyMap ((F.mapHomologicalComplex (ComplexShape.up ℕ)).map φ) n