Fix partial placeholder . in middle of call chain

source/parser/function.civet

@@ -1,6 +1,6 @@
 import type {
+  ArrowFunction
   ASTNode
-  ASTNodeBase
   ASTNodeObject
   BlockStatement
   BreakStatement
@@ -11,11 +11,11 @@ import type {
   IterationExpression
   IterationFamily
   IterationStatement
+  NewExpression
   Parameter
   ParametersNode
   StatementTuple
   SwitchStatement
-  TypeIdentifier
   TypeNode
   Whitespace
 } from ./types.civet
@@ -30,6 +30,10 @@ import {
   gatherBindingCode
 } from ./binding.civet
 
+import {
+  replaceNode
+} from ./lib.civet
+
 import {
   findAncestor
   findChildIndex
@@ -806,6 +810,29 @@ function makeAmpersandFunction(rhs: AmpersandBlockBody): ASTNode
 
   fn
 
+/**
+Split a CallExpression node in half, where the inner half ends with child
+number given by `index`.  Returns the inner call.
+*/
+function splitCall(call: CallExpression, index: number): CallExpression | NewExpression
+  subcall: CallExpression := makeNode
+    type: "CallExpression"
+    children: call.children[0..index]
+  call.children[0..index] = [subcall]
+  subcall.parent = call
+  { parent } := call
+  // Pull preceding `new` into inner call to preserve semantics
+  if parent is like {type: "NewExpression", expression: ^call}
+    replaceNode parent, call
+    parent.parent = call
+    parent.expression = subcall
+    parent.children = parent.children.map & is call ? subcall : &
+    subcall.parent = parent
+    call.children[0] = parent
+    parent
+  else
+    subcall
+
 export {
   assignResults
   expressionizeIteration
@@ -815,5 +842,6 @@ export {
   processFunctions
   processReturn
   skipImplicitArguments
+  splitCall
   wrapIterationReturningResults
 }

source/parser/lib.civet

@@ -71,6 +71,7 @@ import {
   prepend
   stripTrailingImplicitComma
   trimFirstSpace
+  updateParentPointers
   wrapIIFE
   wrapWithReturn
 } from ./util.civet
@@ -110,6 +111,7 @@ import {
   processCoffeeDo
   processFunctions
   skipImplicitArguments
+  splitCall
 } from ./function.civet
 import { processPatternMatching } from ./pattern-matching.civet
 import {
@@ -1296,7 +1298,12 @@ function processPlaceholders(statements: StatementTuple[]): void
       // Partial placeholder . lifts to the nearest call expression,
       // including the call itself and any surrounding unary operations.
       { ancestor } = findAncestor exp, .type is "Call"
+      call := ancestor
       ancestor = ancestor?.parent
+      if ancestor is like {type: "CallExpression"}
+        index := findChildIndex ancestor, call
+        if index < ancestor.children# - 1  // not the last call
+          ancestor = splitCall ancestor, index
       while ancestor?.parent?.type is "UnaryExpression" or ancestor?.parent?.type is "NewExpression"
         ancestor = ancestor.parent
       unless ancestor

source/parser/types.civet

@@ -239,6 +239,7 @@ export type NewExpression
   type: "NewExpression"
   children: Children
   parent?: Parent
+  expression: ASTNode
 
 export type Yield
   type: "Yield"
@@ -368,29 +369,34 @@ export type CaseBlock
   type: "CaseBlock"
   clauses: (PatternClause | CaseClause | WhenClause | DefaultClause)[]
   children: Children
+  parent?: Parent
 
 export type PatternClause
   type: "PatternClause"
   children: Children
+  parent?: Parent
   patterns: PatternExpression[]
   block: BlockStatement
 
 export type CaseClause
   type: "CaseClause"
   children: Children
+  parent?: Parent
   cases: ASTNode[]
   block: BlockStatement
 
 export type WhenClause
   type: "WhenClause"
   children: Children
+  parent?: Parent
   cases: ASTNode[]
   break: ASTNode
   block: BlockStatement
 
 export type DefaultClause
   type: "DefaultClause"
   children: Children
+  parent?: Parent
   block: BlockStatement
 
 export type EmptyStatement
@@ -454,6 +460,7 @@ export type AtBinding =
   type: "AtBinding"
   ref: ASTRef
   children: Children & [ASTRef]
+  parent?: Parent
 
 export type BlockStatement =
   type: "BlockStatement"
@@ -480,6 +487,7 @@ export type DeclarationStatement =
 export type Binding =
   type: "Binding"
   children: Children
+  parent?: Parent
   names: string[]
   pattern: BindingIdentifier | BindingPattern
   typeSuffix: TypeSuffix?
@@ -620,6 +628,7 @@ export type Placeholder =
 export type PinPattern =
   type: "PinPattern"
   children: Children
+  parent?: Parent
   expression: ExpressionNode
 
 // _?, __
@@ -683,6 +692,7 @@ export type ObjectBindingPatternContent =
 export type ObjectBindingPattern =
   type: "ObjectBindingPattern",
   children: Children & [Whitespace, ASTLeaf, ObjectBindingPatternContent, WSNode, ASTLeaf]
+  parent?: Parent
   names: string[]
   properties: ObjectBindingPatternContent
   typeSuffix?: TypeSuffix?
@@ -799,6 +809,7 @@ export type TypeSuffix =
   nonnull?: ASTNode
   t?: ASTNode
   children: Children
+  parent?: Parent
 
 export type ReturnTypeAnnotation =
   type: "ReturnTypeAnnotation"

test/partial-placeholder.civet

@@ -33,6 +33,14 @@ describe "partial placeholder", ->
     $ => f()?.g?.().h($, x)
   """
 
+  testCase """
+    not last call in chain
+    ---
+    f(a)(b)(.)(c)(d)
+    ---
+    ($ => f(a)(b)($))(c)(d)
+  """
+
   testCase """
     object value
     ---
@@ -101,6 +109,14 @@ describe "partial placeholder", ->
     $ => new X($)
   """
 
+  testCase """
+    not last call in new chain
+    ---
+    new T(a)(b)(.)(c)(d)
+    ---
+    ($ => new T(a)(b)($))(c)(d)
+  """
+
   testCase """
     in larger expression
     ---