Allow imports in declare module

src/parser/statement.js

@@ -1016,7 +1016,7 @@ pp.parseExportSpecifiers = function () {
 // Parses import declaration.
 
 pp.parseImport = function (node) {
-  this.next();
+  this.eat(tt._import);
 
   // import '...'
   if (this.match(tt.string)) {

src/plugins/flow.js

@@ -95,11 +95,22 @@ pp.flowParseDeclareModule = function (node) {
   const body = bodyNode.body = [];
   this.expect(tt.braceL);
   while (!this.match(tt.braceR)) {
-    const node2 = this.startNode();
+    let bodyNode = this.startNode();
 
-    this.expectContextual("declare", "Unexpected token. Only declares are allowed inside declare module");
+    if (this.match(tt._import)) {
+      const lookahead = this.lookahead();
+      if (lookahead.value !== "type" && lookahead.value !== "typeof") {
+        this.unexpected(null, "Imports within a `declare module` body must always be `import type` or `import typeof`");
+      }
+
+      this.parseImport(bodyNode);
+    } else {
+      this.expectContextual("declare", "Only declares and type imports are allowed inside declare module");
+
+      bodyNode = this.flowParseDeclare(bodyNode, true);
+    }
 
-    body.push(this.flowParseDeclare(node2));
+    body.push(bodyNode);
   }
   this.expect(tt.braceR);
 

test/fixtures/flow/declare-module/8/options.json

@@ -1,3 +1,3 @@
 {
-  "throws": "Unexpected token. Only declares are allowed inside declare module (2:2)"
+  "throws": "Only declares and type imports are allowed inside declare module (2:2)"
 }

test/fixtures/flow/declare-module/import/actual.js

@@ -0,0 +1 @@
+declare module "M" { import type T from "TM"; }

test/fixtures/flow/declare-module/import/expected.json

@@ -0,0 +1,156 @@
+{
+  "type": "File",
+  "start": 0,
+  "end": 47,
+  "loc": {
+    "start": {
+      "line": 1,
+      "column": 0
+    },
+    "end": {
+      "line": 1,
+      "column": 47
+    }
+  },
+  "program": {
+    "type": "Program",
+    "start": 0,
+    "end": 47,
+    "loc": {
+      "start": {
+        "line": 1,
+        "column": 0
+      },
+      "end": {
+        "line": 1,
+        "column": 47
+      }
+    },
+    "sourceType": "module",
+    "body": [
+      {
+        "type": "DeclareModule",
+        "start": 0,
+        "end": 47,
+        "loc": {
+          "start": {
+            "line": 1,
+            "column": 0
+          },
+          "end": {
+            "line": 1,
+            "column": 47
+          }
+        },
+        "id": {
+          "type": "StringLiteral",
+          "start": 15,
+          "end": 18,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 15
+            },
+            "end": {
+              "line": 1,
+              "column": 18
+            }
+          },
+          "extra": {
+            "rawValue": "M",
+            "raw": "\"M\""
+          },
+          "value": "M"
+        },
+        "body": {
+          "type": "BlockStatement",
+          "start": 19,
+          "end": 47,
+          "loc": {
+            "start": {
+              "line": 1,
+              "column": 19
+            },
+            "end": {
+              "line": 1,
+              "column": 47
+            }
+          },
+          "body": [
+            {
+              "type": "ImportDeclaration",
+              "start": 21,
+              "end": 45,
+              "loc": {
+                "start": {
+                  "line": 1,
+                  "column": 21
+                },
+                "end": {
+                  "line": 1,
+                  "column": 45
+                }
+              },
+              "specifiers": [
+                {
+                  "type": "ImportDefaultSpecifier",
+                  "start": 33,
+                  "end": 34,
+                  "loc": {
+                    "start": {
+                      "line": 1,
+                      "column": 33
+                    },
+                    "end": {
+                      "line": 1,
+                      "column": 34
+                    }
+                  },
+                  "local": {
+                    "type": "Identifier",
+                    "start": 33,
+                    "end": 34,
+                    "loc": {
+                      "start": {
+                        "line": 1,
+                        "column": 33
+                      },
+                      "end": {
+                        "line": 1,
+                        "column": 34
+                      },
+                      "identifierName": "T"
+                    },
+                    "name": "T"
+                  }
+                }
+              ],
+              "importKind": "type",
+              "source": {
+                "type": "StringLiteral",
+                "start": 40,
+                "end": 44,
+                "loc": {
+                  "start": {
+                    "line": 1,
+                    "column": 40
+                  },
+                  "end": {
+                    "line": 1,
+                    "column": 44
+                  }
+                },
+                "extra": {
+                  "rawValue": "TM",
+                  "raw": "\"TM\""
+                },
+                "value": "TM"
+              }
+            }
+          ]
+        }
+      }
+    ],
+    "directives": []
+  }
+}

test/fixtures/flow/declare-module/invalid-import/actual.js

@@ -0,0 +1 @@
+declare module "M" { import T from "TM"; }

test/fixtures/flow/declare-module/invalid-import/options.json

@@ -0,0 +1,3 @@
+{
+  "throws": "Imports within a `declare module` body must always be `import type` or `import typeof` (1:21)"
+}