Rename longest_chain to longestChain for convention

lean/Spa/Lattice/AboveBelow.lean

@@ -273,7 +273,7 @@ instance [Inhabited α] : FiniteHeightLattice (AboveBelow α) where
   bot := bot
   top := top
   height := 2
-  longest_chain :=
+  longestChain :=
     { series :=
         ((RelSeries.singleton _ bot).snoc (mk default)
             (by rw [RelSeries.last_singleton]; exact bot_lt_mk default)).snoc top

lean/Spa/Lattice/Prod.lean

@@ -68,25 +68,25 @@ instance prod [A : FiniteHeightLattice α] [B : FiniteHeightLattice β] :
   bot := ((⊥ : α), (⊥ : β))
   top := ((⊤ : α), (⊤ : β))
   height := A.height + B.height
-  longest_chain :=
+  longestChain :=
     { series :=
         RelSeries.smash
-          (A.longest_chain.series.map (fun a => (a, (⊥ : β)))
+          (A.longestChain.series.map (fun a => (a, (⊥ : β)))
             (fun _ _ h => Prod.mk_lt_mk_iff_left.mpr h))
-          (B.longest_chain.series.map (fun b => ((⊤ : α), b))
+          (B.longestChain.series.map (fun b => ((⊤ : α), b))
             (fun _ _ h => Prod.mk_lt_mk_iff_right.mpr h))
-          (by simp [A.longest_chain.last_series, B.longest_chain.head_series])
+          (by simp [A.longestChain.last_series, B.longestChain.head_series])
       head_series :=
         (RelSeries.head_smash _).trans
           ((LTSeries.head_map _ _ _).trans
-            (congrArg (·, (⊥ : β)) A.longest_chain.head_series))
+            (congrArg (·, (⊥ : β)) A.longestChain.head_series))
       last_series :=
         (RelSeries.last_smash _).trans
           ((LTSeries.last_map _ _ _).trans
-            (congrArg ((⊤ : α), ·) B.longest_chain.last_series))
+            (congrArg ((⊤ : α), ·) B.longestChain.last_series))
       length_series := by
-        show A.longest_chain.series.length + B.longest_chain.series.length = _
-        rw [A.longest_chain.length_series, B.longest_chain.length_series] }
+        show A.longestChain.series.length + B.longestChain.series.length = _
+        rw [A.longestChain.length_series, B.longestChain.length_series] }
   chains_bounded := fun c => by
     obtain ⟨c₁, c₂, -, -, -, -, hlen⟩ := LTSeries.exists_unzip c
     have h₁ := A.chains_bounded c₁

lean/Spa/Lattice/Unit.lean

@@ -22,7 +22,7 @@ instance : FiniteHeightLattice PUnit where
   bot := PUnit.unit
   top := PUnit.unit
   height := 0
-  longest_chain := { series := RelSeries.singleton _ PUnit.unit, head_series := refl _, last_series := refl _, length_series := refl _ }
+  longestChain := { series := RelSeries.singleton _ PUnit.unit, head_series := refl _, last_series := refl _, length_series := refl _ }
   chains_bounded := boundedChains_of_subsingleton PUnit 0
 
 end Spa