Class prototype property AST

src/nodes.coffee

@@ -2694,6 +2694,8 @@ exports.Class = class Class extends Base
       @addInitializerMethod node
     else if not o.compiling and @validClassProperty node
       @addClassProperty node
+    else if not o.compiling and @validClassPrototypeProperty node
+      @addClassPrototypeProperty node
     else
       null
 
@@ -2736,6 +2738,17 @@ exports.Class = class Class extends Base
       operatorToken
     }).withLocationDataFrom assign
 
+  validClassPrototypeProperty: (node) ->
+    return no unless node instanceof Assign
+    node.context is 'object' and not node.variable.hasProperties()
+
+  addClassPrototypeProperty: (assign) ->
+    {variable, value} = assign
+    new ClassPrototypeProperty({
+      name: variable.base
+      value
+    }).withLocationDataFrom assign
+
   makeDefaultConstructor: ->
     ctor = @addInitializerMethod new Assign (new Value new PropertyName 'constructor'), new Code
     @body.unshift ctor
@@ -2883,7 +2896,11 @@ exports.ExecutableClassBody = class ExecutableClassBody extends Base
         # The class scope is not available yet, so return the assignment to update later
         assign = @externalCtor = new Assign new Value, value
       else if not assign.variable.this
-        name      = new (if base.shouldCache() then Index else Access) base
+        name =
+          if base instanceof ComputedPropertyName
+            new Index base.value
+          else
+            new (if base.shouldCache() then Index else Access) base
         prototype = new Access new PropertyName 'prototype'
         variable  = new Value new ThisLiteral(), [ prototype, name ]
 
@@ -2911,6 +2928,20 @@ exports.ClassProperty = class ClassProperty extends Base
       operator: @operatorToken?.value ? '='
       staticClassName: @staticClassName?.ast(o) ? null
 
+exports.ClassPrototypeProperty = class ClassPrototypeProperty extends Base
+  constructor: ({@name, @value}) ->
+    super()
+
+  children: ['name', 'value']
+
+  isStatement: YES
+
+  astProperties: (o) ->
+    return
+      key: @name.ast o, LEVEL_LIST
+      value: @value.ast o, LEVEL_LIST
+      computed: @name instanceof ComputedPropertyName
+
 #### Import and Export
 
 exports.ModuleDeclaration = class ModuleDeclaration extends Base

test/abstract_syntax_tree.coffee

@@ -1475,6 +1475,28 @@ test "AST as expected for Class node", ->
           shorthand: no
       ]
 
+  testStatement '''
+    class A
+      b: 1
+      [c]: 2
+  ''',
+    type: 'ClassDeclaration'
+    id: ID 'A'
+    superClass: null
+    body:
+      type: 'ClassBody'
+      body: [
+        type: 'ClassPrototypeProperty'
+        key: ID 'b'
+        value: NUMBER 1
+        computed: no
+      ,
+        type: 'ClassPrototypeProperty'
+        key: ID 'c'
+        value: NUMBER 2
+        computed: yes
+      ]
+
 # test "AST as expected for ExecutableClassBody node", ->
 #   code = """
 #     class Klass

test/abstract_syntax_tree_location_data.coffee

@@ -7010,3 +7010,98 @@ test "AST as expected for Class node", ->
       end:
         line: 9
         column: 12
+
+  testAstLocationData '''
+    class A
+      b: 1
+      [c]: 2
+  ''',
+    type: 'ClassDeclaration'
+    body:
+      body: [
+        key:
+          start: 10
+          end: 11
+          range: [10, 11]
+          loc:
+            start:
+              line: 2
+              column: 2
+            end:
+              line: 2
+              column: 3
+        value:
+          start: 13
+          end: 14
+          range: [13, 14]
+          loc:
+            start:
+              line: 2
+              column: 5
+            end:
+              line: 2
+              column: 6
+        start: 10
+        end: 14
+        range: [10, 14]
+        loc:
+          start:
+            line: 2
+            column: 2
+          end:
+            line: 2
+            column: 6
+      ,
+        key:
+          start: 18
+          end: 19
+          range: [18, 19]
+          loc:
+            start:
+              line: 3
+              column: 3
+            end:
+              line: 3
+              column: 4
+        value:
+          start: 22
+          end: 23
+          range: [22, 23]
+          loc:
+            start:
+              line: 3
+              column: 7
+            end:
+              line: 3
+              column: 8
+        start: 17
+        end: 23
+        range: [17, 23]
+        loc:
+          start:
+            line: 3
+            column: 2
+          end:
+            line: 3
+            column: 8
+      ]
+      start: 8
+      end: 23
+      range: [8, 23]
+      loc:
+        start:
+          line: 2
+          column: 0
+        end:
+          line: 3
+          column: 8
+    start: 0
+    end: 23
+    range: [0, 23]
+    loc:
+      start:
+        line: 1
+        column: 0
+      end:
+        line: 3
+        column: 8

test/classes.coffee

@@ -1930,3 +1930,11 @@ test "#5085: Bug: @ reference to class not maintained in do block", ->
 
   eq thisFoo, 'foo assigned in class'
   eq thisBar, 'foo assigned in class'
+
+test "#5204: Computed class property", ->
+  foo = 'bar'
+  class A
+    [foo]: 'baz'
+  a = new A()
+  eq a.bar, 'baz'
+  eq A::bar, 'baz'