From 60854525b959927fb36a3c89033d50643c0add51 Mon Sep 17 00:00:00 2001
From: Leni Aniva <v@leni.sh>
Date: Sun, 29 Oct 2023 12:50:36 -0700
Subject: [PATCH] feat: Simplify printing of function applications

---
 Pantograph/Serial.lean | 34 +++++++---------------------------
 Test/Integration.lean  |  2 +-
 Test/Serial.lean       |  4 ++--
 3 files changed, 10 insertions(+), 30 deletions(-)

diff --git a/Pantograph/Serial.lean b/Pantograph/Serial.lean
index 89bc076..63f5949 100644
--- a/Pantograph/Serial.lean
+++ b/Pantograph/Serial.lean
@@ -55,26 +55,8 @@ def name_to_ast (name: Name) (sanitize: Bool := true): String :=
     let quote := "̈̈\""
     if n.contains Lean.idBeginEscape then s!"{quote}{n}{quote}" else n
 
-private def level_depth: Level → Nat
-  | .zero => 0
-  | .succ l => 1 + (level_depth l)
-  | .max u v | .imax u v => 1 + max (level_depth u) (level_depth v)
-  | .param _ | .mvar _ => 0
-
-theorem level_depth_max_imax (u v: Level): (level_depth (Level.max u v) = level_depth (Level.imax u v)) := by
-  constructor
-theorem level_max_depth_decrease (u v: Level): (level_depth u < level_depth (Level.max u v)) := by
-  have h1: level_depth (Level.max u v) = 1 + Nat.max (level_depth u) (level_depth v) := by constructor
-  rewrite [h1]
-  simp_arith
-  conv =>
-    rhs
-    apply Nat.max_def
-  sorry
-theorem level_offset_decrease (u v: Level): (level_depth u ≤ level_depth (Level.max u v).getLevelOffset) := sorry
-
 /-- serialize a sort level. Expression is optimized to be compact e.g. `(+ u 2)` -/
-def serialize_sort_level_ast (level: Level): String :=
+partial def serialize_sort_level_ast (level: Level): String :=
   let k := level.getOffset
   let u := level.getLevelOffset
   let u_str := match u with
@@ -98,14 +80,11 @@ def serialize_sort_level_ast (level: Level): String :=
   | 0, _ => u_str
   | _, .zero => s!"{k}"
   | _, _ => s!"(+ {u_str} {k})"
-  termination_by serialize_sort_level_ast level => level_depth level
-  decreasing_by
-  . sorry
 
 /--
  Completely serializes an expression tree. Json not used due to compactness
 -/
-def serialize_expression_ast (expr: Expr) (sanitize: Bool := true): String :=
+partial def serialize_expression_ast (expr: Expr) (sanitize: Bool := true): String :=
   self expr
   where
   self (e: Expr): String :=
@@ -128,10 +107,11 @@ def serialize_expression_ast (expr: Expr) (sanitize: Bool := true): String :=
       -- The universe level of the const expression is elided since it should be
       -- inferrable from surrounding expression
       s!"(:c {declName})"
-    | .app fn arg =>
-      let fn' := self fn
-      let arg' := self arg
-      s!"({fn'} {arg'})"
+    | .app _ _ =>
+      let fn' := self e.getAppFn
+      let args := e.getAppArgs.map self |>.toList
+      let args := " ".intercalate args
+      s!"({fn'} {args})"
     | .lam binderName binderType body binderInfo =>
       let binderName' := of_name binderName
       let binderType' := self binderType
diff --git a/Test/Integration.lean b/Test/Integration.lean
index a77cb12..6400cca 100644
--- a/Test/Integration.lean
+++ b/Test/Integration.lean
@@ -45,7 +45,7 @@ def subroutine_runner (steps: List (MainM LSpec.TestSeq)): IO LSpec.TestSeq := d
 
 def test_option_modify : IO LSpec.TestSeq :=
   let pp? := Option.some "∀ (n : Nat), n + 1 = Nat.succ n"
-  let sexp? := Option.some "(:forall n (:c Nat) ((((:c Eq) (:c Nat)) (((((((:c HAdd.hAdd) (:c Nat)) (:c Nat)) (:c Nat)) (((:c instHAdd) (:c Nat)) (:c instAddNat))) 0) ((((:c OfNat.ofNat) (:c Nat)) (:lit 1)) ((:c instOfNatNat) (:lit 1))))) ((:c Nat.succ) 0)))"
+  let sexp? := Option.some "(:forall n (:c Nat) ((:c Eq) (:c Nat) ((:c HAdd.hAdd) (:c Nat) (:c Nat) (:c Nat) ((:c instHAdd) (:c Nat) (:c instAddNat)) 0 ((:c OfNat.ofNat) (:c Nat) (:lit 1) ((:c instOfNatNat) (:lit 1)))) ((:c Nat.succ) 0)))"
   let module? := Option.some "Init.Data.Nat.Basic"
   let options: Protocol.Options := {}
   subroutine_runner [
diff --git a/Test/Serial.lean b/Test/Serial.lean
index 575749d..f1b0a9d 100644
--- a/Test/Serial.lean
+++ b/Test/Serial.lean
@@ -45,8 +45,8 @@ def test_sexp_of_symbol (env: Environment): IO LSpec.TestSeq := do
     -- This one contains unhygienic variable names which must be suppressed
     ("Nat.add", "(:forall _ (:c Nat) (:forall _ (:c Nat) (:c Nat)))"),
     -- These ones are normal and easy
-    ("Nat.add_one", "(:forall n (:c Nat) ((((:c Eq) (:c Nat)) (((((((:c HAdd.hAdd) (:c Nat)) (:c Nat)) (:c Nat)) (((:c instHAdd) (:c Nat)) (:c instAddNat))) 0) ((((:c OfNat.ofNat) (:c Nat)) (:lit 1)) ((:c instOfNatNat) (:lit 1))))) ((:c Nat.succ) 0)))"),
-    ("Nat.le_of_succ_le", "(:forall n (:c Nat) (:forall m (:c Nat) (:forall h (((((:c LE.le) (:c Nat)) (:c instLENat)) ((:c Nat.succ) 1)) 0) (((((:c LE.le) (:c Nat)) (:c instLENat)) 2) 1)) :implicit) :implicit)"),
+    ("Nat.add_one", "(:forall n (:c Nat) ((:c Eq) (:c Nat) ((:c HAdd.hAdd) (:c Nat) (:c Nat) (:c Nat) ((:c instHAdd) (:c Nat) (:c instAddNat)) 0 ((:c OfNat.ofNat) (:c Nat) (:lit 1) ((:c instOfNatNat) (:lit 1)))) ((:c Nat.succ) 0)))"),
+    ("Nat.le_of_succ_le", "(:forall n (:c Nat) (:forall m (:c Nat) (:forall h ((:c LE.le) (:c Nat) (:c instLENat) ((:c Nat.succ) 1) 0) ((:c LE.le) (:c Nat) (:c instLENat) 2 1)) :implicit) :implicit)"),
     -- Handling of higher order types
     ("Or", "(:forall a (:sort 0) (:forall b (:sort 0) (:sort 0)))"),
     ("List", "(:forall α (:sort (+ u 1)) (:sort (+ u 1)))")