Fix declare class with qualified type identifier (#97)

This makes declare class extends behave the same way as in flow
The ast-token after the extends keyword, might be either Identifier or
QualifiedTypeIdentifier

To do that this commits splits the parseGenericType into two functions,
one for parsing genericType and on for qualifiedTypeIdentifier

src/plugins/flow.js

@@ -165,7 +165,7 @@ pp.flowParseInterfaceish = function (node, allowStatic) {
 pp.flowParseInterfaceExtends = function () {
   let node = this.startNode();
 
-  node.id = this.parseIdentifier();
+  node.id = this.flowParseQualifiedTypeIdentifier();
   if (this.isRelational("<")) {
     node.typeParameters = this.flowParseTypeParameterInstantiation();
   } else {
@@ -394,19 +394,27 @@ pp.flowObjectTypeSemicolon = function () {
   }
 };
 
-pp.flowParseGenericType = function (startPos, startLoc, id) {
-  let node = this.startNodeAt(startPos, startLoc);
-
-  node.typeParameters = null;
-  node.id = id;
+pp.flowParseQualifiedTypeIdentifier = function (startPos, startLoc, id) {
+  startPos = startPos || this.state.start;
+  startLoc = startLoc || this.state.startLoc;
+  let node = id || this.parseIdentifier();
 
   while (this.eat(tt.dot)) {
     let node2 = this.startNodeAt(startPos, startLoc);
-    node2.qualification = node.id;
+    node2.qualification = node;
     node2.id = this.parseIdentifier();
-    node.id = this.finishNode(node2, "QualifiedTypeIdentifier");
+    node = this.finishNode(node2, "QualifiedTypeIdentifier");
   }
 
+  return node;
+};
+
+pp.flowParseGenericType = function (startPos, startLoc, id) {
+  let node = this.startNodeAt(startPos, startLoc);
+
+  node.typeParameters = null;
+  node.id = this.flowParseQualifiedTypeIdentifier(startPos, startLoc, id);
+
   if (this.isRelational("<")) {
     node.typeParameters = this.flowParseTypeParameterInstantiation();
   }

test/fixtures/flow/declare-statements/16/actual.js

@@ -0,0 +1 @@
+declare class A extends C.B.D { }

test/fixtures/flow/declare-statements/16/expected.json

@@ -0,0 +1,185 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 33,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 1,
+      "column": 33
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 33,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 1,
+        "column": 33
+      }
+    },
+    "sourceType": "module",
+    "body": [
+      {
+        "type": "DeclareClass",
+        "start": 0,
+        "end": 33,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 33
+          }
+        },
+        "id": {
+          "type": "Identifier",
+          "start": 14,
+          "end": 15,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 14
+            },
+            "end": {
+              "line": 1,
+              "column": 15
+            },
+            "identifierName": "A"
+          },
+          "name": "A"
+        },
+        "typeParameters": null,
+        "extends": [
+          {
+            "type": "InterfaceExtends",
+            "start": 24,
+            "end": 29,
+            "loc": {
+              "start": {
+                "line": 1,
+                "column": 24
+              },
+              "end": {
+                "line": 1,
+                "column": 29
+              }
+            },
+            "id": {
+              "type": "QualifiedTypeIdentifier",
+              "start": 24,
+              "end": 29,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 24
+                },
+                "end": {
+                  "line": 1,
+                  "column": 29
+                }
+              },
+              "qualification": {
+                "type": "QualifiedTypeIdentifier",
+                "start": 24,
+                "end": 27,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 24
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 27
+                  }
+                },
+                "qualification": {
+                  "type": "Identifier",
+                  "start": 24,
+                  "end": 25,
+                  "loc": {
+                    "start": {
+                      "line": 1,
+                      "column": 24
+                    },
+                    "end": {
+                      "line": 1,
+                      "column": 25
+                    },
+                    "identifierName": "C"
+                  },
+                  "name": "C"
+                },
+                "id": {
+                  "type": "Identifier",
+                  "start": 26,
+                  "end": 27,
+                  "loc": {
+                    "start": {
+                      "line": 1,
+                      "column": 26
+                    },
+                    "end": {
+                      "line": 1,
+                      "column": 27
+                    },
+                    "identifierName": "B"
+                  },
+                  "name": "B"
+                }
+              },
+              "id": {
+                "type": "Identifier",
+                "start": 28,
+                "end": 29,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 28
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 29
+                  },
+                  "identifierName": "D"
+                },
+                "name": "D"
+              }
+            },
+            "typeParameters": null
+          }
+        ],
+        "mixins": [],
+        "body": {
+          "type": "ObjectTypeAnnotation",
+          "start": 30,
+          "end": 33,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 30
+            },
+            "end": {
+              "line": 1,
+              "column": 33
+            }
+          },
+          "callProperties": [],
+          "properties": [],
+          "indexers": []
+        }
+      }
+    ],
+    "directives": []
+  }
+}