Flow Enums with unknown members support

packages/babel-generator/src/generators/flow.ts

@@ -195,6 +195,10 @@ function enumBody(context: any, node: any) {
     context.print(member, node);
     context.newline();
   }
+  if (node.hasUnknownMembers) {
+    context.token("...");
+    context.newline();
+  }
   context.dedent();
   context.token("}");
 }

packages/babel-generator/test/fixtures/flow/enum-declaration/input.js

@@ -34,3 +34,9 @@ enum E of symbol {
   A,
   B,
 }
+
+enum E {
+  A,
+  B,
+  ...
+}

packages/babel-generator/test/fixtures/flow/enum-declaration/output.js

@@ -34,3 +34,8 @@ enum E of symbol {
   A,
   B,
 }
+enum E {
+  A,
+  B,
+  ...
+}

packages/babel-parser/src/plugins/flow/index.js

@@ -3282,10 +3282,13 @@ export default (superClass: Class<Parser>): Class<Parser> =>
       enumName: string,
       explicitType: EnumExplicitType,
     }): {|
-      booleanMembers: Array<N.Node>,
-      numberMembers: Array<N.Node>,
-      stringMembers: Array<N.Node>,
-      defaultedMembers: Array<N.Node>,
+      members: {|
+        booleanMembers: Array<N.Node>,
+        numberMembers: Array<N.Node>,
+        stringMembers: Array<N.Node>,
+        defaultedMembers: Array<N.Node>,
+      |},
+      hasUnknownMembers: boolean,
     |} {
       const seenNames = new Set();
       const members = {
@@ -3294,7 +3297,12 @@ export default (superClass: Class<Parser>): Class<Parser> =>
         stringMembers: [],
         defaultedMembers: [],
       };
+      let hasUnknownMembers = false;
       while (!this.match(tt.braceR)) {
+        if (this.eat(tt.ellipsis)) {
+          hasUnknownMembers = true;
+          break;
+        }
         const memberNode = this.startNode();
         const { id, init } = this.flowEnumMemberRaw();
         const memberName = id.name;
@@ -3371,7 +3379,7 @@ export default (superClass: Class<Parser>): Class<Parser> =>
           this.expect(tt.comma);
         }
       }
-      return members;
+      return { members, hasUnknownMembers };
     }
 
     flowEnumStringMembers(
@@ -3438,7 +3446,11 @@ export default (superClass: Class<Parser>): Class<Parser> =>
     flowEnumBody(node: N.Node, { enumName, nameLoc }): N.Node {
       const explicitType = this.flowEnumParseExplicitType({ enumName });
       this.expect(tt.braceL);
-      const members = this.flowEnumMembers({ enumName, explicitType });
+      const { members, hasUnknownMembers } = this.flowEnumMembers({
+        enumName,
+        explicitType,
+      });
+      node.hasUnknownMembers = hasUnknownMembers;
 
       switch (explicitType) {
         case "boolean":

packages/babel-parser/test/fixtures/flow/enum-declaration/boolean-explicit/output.json

@@ -48,7 +48,8 @@
                 "value": false
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/boolean-implicit/output.json

@@ -19,6 +19,7 @@
           "type": "EnumBooleanBody",
           "start":7,"end":35,"loc":{"start":{"line":1,"column":7},"end":{"line":4,"column":1}},
           "explicitType": false,
+          "hasUnknownMembers": false,
           "members": [
             {
               "type": "EnumBooleanMember",

packages/babel-parser/test/fixtures/flow/enum-declaration/boolean-member-not-initialized-explicit/output.json

@@ -22,7 +22,8 @@
           "type": "EnumBooleanBody",
           "start":7,"end":26,"loc":{"start":{"line":1,"column":7},"end":{"line":3,"column":1}},
           "explicitType": true,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/boolean-member-not-initialized-implicit/output.json

@@ -22,6 +22,7 @@
           "type": "EnumBooleanBody",
           "start":7,"end":27,"loc":{"start":{"line":1,"column":7},"end":{"line":4,"column":1}},
           "explicitType": false,
+          "hasUnknownMembers": false,
           "members": [
             {
               "type": "EnumBooleanMember",

packages/babel-parser/test/fixtures/flow/enum-declaration/duplicate-member-name/output.json

@@ -41,7 +41,8 @@
                 "name": "A"
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/empty/output.json

@@ -19,7 +19,8 @@
           "type": "EnumStringBody",
           "start":7,"end":10,"loc":{"start":{"line":1,"column":7},"end":{"line":1,"column":10}},
           "explicitType": false,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/enum-name/output.json

@@ -19,7 +19,8 @@
           "type": "EnumStringBody",
           "start":10,"end":13,"loc":{"start":{"line":1,"column":10},"end":{"line":2,"column":1}},
           "explicitType": false,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/export/output.json

@@ -25,7 +25,8 @@
             "type": "EnumStringBody",
             "start":14,"end":16,"loc":{"start":{"line":1,"column":14},"end":{"line":1,"column":16}},
             "explicitType": false,
-            "members": []
+            "members": [],
+            "hasUnknownMembers": false
           }
         }
       },
@@ -44,7 +45,8 @@
             "type": "EnumStringBody",
             "start":40,"end":42,"loc":{"start":{"line":3,"column":22},"end":{"line":3,"column":24}},
             "explicitType": false,
-            "members": []
+            "members": [],
+            "hasUnknownMembers": false
           }
         }
       }

packages/babel-parser/test/fixtures/flow/enum-declaration/inconsistent-member-values-majority-defaulted/output.json

@@ -22,7 +22,8 @@
           "type": "EnumStringBody",
           "start":7,"end":29,"loc":{"start":{"line":1,"column":7},"end":{"line":5,"column":1}},
           "explicitType": false,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/inconsistent-member-values-mixed-initializers/output.json

@@ -22,7 +22,8 @@
           "type": "EnumStringBody",
           "start":7,"end":31,"loc":{"start":{"line":1,"column":7},"end":{"line":4,"column":1}},
           "explicitType": false,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/invalid-explicit-type-identifier/output.json

@@ -22,7 +22,8 @@
           "type": "EnumStringBody",
           "start":7,"end":17,"loc":{"start":{"line":1,"column":7},"end":{"line":2,"column":1}},
           "explicitType": false,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/invalid-member-initializer-boolean-explicit-string/output.json

@@ -22,7 +22,8 @@
           "type": "EnumStringBody",
           "start":7,"end":32,"loc":{"start":{"line":1,"column":7},"end":{"line":3,"column":1}},
           "explicitType": true,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/invalid-member-initializer-literal-explicit-symbol/output.json

@@ -21,7 +21,8 @@
         "body": {
           "type": "EnumSymbolBody",
           "start":7,"end":29,"loc":{"start":{"line":1,"column":7},"end":{"line":3,"column":1}},
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/invalid-member-initializer-number-explicit-boolean/output.json

@@ -22,7 +22,8 @@
           "type": "EnumBooleanBody",
           "start":7,"end":30,"loc":{"start":{"line":1,"column":7},"end":{"line":3,"column":1}},
           "explicitType": true,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/invalid-member-initializer-number-explicit-string/output.json

@@ -22,7 +22,8 @@
           "type": "EnumStringBody",
           "start":7,"end":29,"loc":{"start":{"line":1,"column":7},"end":{"line":3,"column":1}},
           "explicitType": true,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/invalid-member-initializer-string-explicit-boolean/output.json

@@ -22,7 +22,8 @@
           "type": "EnumBooleanBody",
           "start":7,"end":33,"loc":{"start":{"line":1,"column":7},"end":{"line":3,"column":1}},
           "explicitType": true,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/invalid-member-initializer-string-explicit-number/output.json

@@ -22,7 +22,8 @@
           "type": "EnumNumberBody",
           "start":7,"end":32,"loc":{"start":{"line":1,"column":7},"end":{"line":3,"column":1}},
           "explicitType": true,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/invalid-member-name/output.json

@@ -42,7 +42,8 @@
                 "name": "bar"
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/no-trailing-comma/output.json

@@ -29,7 +29,8 @@
                 "name": "A"
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/number-explicit/output.json

@@ -56,7 +56,8 @@
                 "value": 2
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/number-implicit/output.json

@@ -19,6 +19,7 @@
           "type": "EnumNumberBody",
           "start":7,"end":28,"loc":{"start":{"line":1,"column":7},"end":{"line":4,"column":1}},
           "explicitType": false,
+          "hasUnknownMembers": false,
           "members": [
             {
               "type": "EnumNumberMember",

packages/babel-parser/test/fixtures/flow/enum-declaration/number-member-not-initialized-explicit/output.json

@@ -22,7 +22,8 @@
           "type": "EnumNumberBody",
           "start":7,"end":25,"loc":{"start":{"line":1,"column":7},"end":{"line":3,"column":1}},
           "explicitType": true,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/number-member-not-initialized-implicit/output.json

@@ -22,6 +22,7 @@
           "type": "EnumNumberBody",
           "start":7,"end":24,"loc":{"start":{"line":1,"column":7},"end":{"line":4,"column":1}},
           "explicitType": false,
+          "hasUnknownMembers": false,
           "members": [
             {
               "type": "EnumNumberMember",

packages/babel-parser/test/fixtures/flow/enum-declaration/reserved-word-enum-name/output.json

@@ -22,7 +22,8 @@
           "type": "EnumStringBody",
           "start":11,"end":14,"loc":{"start":{"line":1,"column":11},"end":{"line":2,"column":1}},
           "explicitType": false,
-          "members": []
+          "members": [],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/string-explicit-defaulted/output.json

@@ -38,7 +38,8 @@
                 "name": "B"
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/string-explicit-initialized/output.json

@@ -56,7 +56,8 @@
                 "value": "b"
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/string-implicit-defaulted/output.json

@@ -38,7 +38,8 @@
                 "name": "B"
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/string-implicit-initialized/output.json

@@ -56,7 +56,8 @@
                 "value": "b"
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/string-member-inconsistently-initialized-majority-defaulted/output.json

@@ -41,7 +41,8 @@
                 "name": "C"
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/string-member-inconsistently-initialized-majority-initialized/output.json

@@ -59,7 +59,8 @@
                 "value": "c"
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/symbol/output.json

@@ -37,7 +37,8 @@
                 "name": "B"
               }
             }
-          ]
+          ],
+          "hasUnknownMembers": false
         }
       }
     ],

packages/babel-parser/test/fixtures/flow/enum-declaration/unknown-members-invalid/input.js

@@ -0,0 +1,3 @@
+enum E {
+  ...,
+}