fix: support string assertion key in assert entries

packages/babel-parser/src/parser/statement.js

@@ -2182,9 +2182,14 @@ export default class StatementParser extends ExpressionParser {
     node.specifiers.push(this.finishNode(specifier, type));
   }
 
-  parseAssertEntries() {
-    this.expectPlugin("importAssertions");
-
+  /**
+   * parse assert entries
+   *
+   * @see {@link https://tc39.es/proposal-import-assertions/#prod-AssertEntries |AssertEntries}
+   * @returns {N.ImportAttribute[]}
+   * @memberof StatementParser
+   */
+  parseAssertEntries(): N.ImportAttribute[] {
     const attrs = [];
     const attrNames = new Set();
 
@@ -2193,46 +2198,48 @@ export default class StatementParser extends ExpressionParser {
         break;
       }
 
-      const node = this.startNode();
+      const node = this.startNode<N.ImportAttribute>();
 
       // parse AssertionKey : IdentifierName, StringLiteral
-      let assertionKeyNode;
+      const keyName = this.state.value;
       if (this.match(tt.string)) {
-        assertionKeyNode = this.parseLiteral(this.state.value, "StringLiteral");
+        node.key = this.parseLiteral<N.StringLiteral>(keyName, "StringLiteral");
       } else {
-        assertionKeyNode = this.parseIdentifier(true);
+        node.key = this.parseIdentifier(true);
       }
-      this.next();
-      node.key = assertionKeyNode;
+      this.expect(tt.colon);
 
       // for now we are only allowing `type` as the only allowed module attribute
-      if (node.key.name !== "type") {
+      if (keyName !== "type") {
         this.raise(
           node.key.start,
           Errors.ModuleAttributeDifferentFromType,
-          node.key.name,
+          keyName,
         );
       }
       // check if we already have an entry for an attribute
       // if a duplicate entry is found, throw an error
       // for now this logic will come into play only when someone declares `type` twice
-      if (attrNames.has(node.key.name)) {
+      if (attrNames.has(keyName)) {
         this.raise(
           node.key.start,
           Errors.ModuleAttributesWithDuplicateKeys,
-          node.key.name,
+          keyName,
         );
       }
-      attrNames.add(node.key.name);
+      attrNames.add(keyName);
 
       if (!this.match(tt.string)) {
         throw this.unexpected(
           this.state.start,
           Errors.ModuleAttributeInvalidValue,
         );
       }
-      node.value = this.parseLiteral(this.state.value, "StringLiteral");
-      this.finishNode(node, "ImportAttribute");
+      node.value = this.parseLiteral<N.StringLiteral>(
+        this.state.value,
+        "StringLiteral",
+      );
+      this.finishNode<N.ImportAttribute>(node, "ImportAttribute");
       attrs.push(node);
     } while (this.eat(tt.comma));
 
@@ -2291,18 +2298,15 @@ export default class StatementParser extends ExpressionParser {
   }
 
   maybeParseImportAssertions() {
-    if (
-      this.match(tt.name) &&
-      this.state.value === "assert" &&
-      !this.hasPrecedingLineBreak()
-    ) {
+    // [no LineTerminator here] AssertClause
+    if (this.isContextual("assert") && !this.hasPrecedingLineBreak()) {
       this.expectPlugin("importAssertions");
-      this.next();
+      this.next(); // eat `assert`
     } else {
       if (this.hasPlugin("importAssertions")) return [];
       return null;
     }
-
+    // https://tc39.es/proposal-import-assertions/#prod-AssertClause
     this.eat(tt.braceL);
     const attrs = this.parseAssertEntries();
     this.eat(tt.braceR);

packages/babel-parser/test/fixtures/experimental/import-assertions/invalid-assert-entry-no-colon/input.js

@@ -0,0 +1 @@
+import "foo" assert { type, "json" };

packages/babel-parser/test/fixtures/experimental/import-assertions/invalid-assert-entry-no-colon/options.json

@@ -0,0 +1,9 @@
+{
+  "plugins": [
+    [
+      "importAssertions"
+    ]
+  ],
+  "sourceType": "module",
+  "throws": "Unexpected token, expected \":\" (1:26)"
+}

packages/babel-parser/test/fixtures/experimental/import-assertions/invalid-escaped-assert/input.js

@@ -0,0 +1 @@
+import "foo" \u{61}ssert { type: "json" };

packages/babel-parser/test/fixtures/experimental/import-assertions/invalid-escaped-assert/options.json

@@ -0,0 +1,9 @@
+{
+  "plugins": [
+    [
+      "importAssertions"
+    ]
+  ],
+  "sourceType": "module",
+  "throws": "Unexpected token, expected \";\" (1:13)"
+}

packages/babel-parser/test/fixtures/experimental/import-assertions/invalid-syntax-with-repeated-type-string/input.js

@@ -0,0 +1 @@
+import foo from "foo.json" assert { "type": "json", type: "html", "type": "js" };

packages/babel-parser/test/fixtures/experimental/import-assertions/invalid-syntax-with-repeated-type-string/output.json

@@ -0,0 +1,105 @@
+{
+  "type": "File",
+  "start":0,"end":81,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":81}},
+  "errors": [
+    "SyntaxError: Duplicate key \"type\" is not allowed in module attributes (1:52)",
+    "SyntaxError: Duplicate key \"type\" is not allowed in module attributes (1:66)"
+  ],
+  "program": {
+    "type": "Program",
+    "start":0,"end":81,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":81}},
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ImportDeclaration",
+        "start":0,"end":81,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":81}},
+        "specifiers": [
+          {
+            "type": "ImportDefaultSpecifier",
+            "start":7,"end":10,"loc":{"start":{"line":1,"column":7},"end":{"line":1,"column":10}},
+            "local": {
+              "type": "Identifier",
+              "start":7,"end":10,"loc":{"start":{"line":1,"column":7},"end":{"line":1,"column":10},"identifierName":"foo"},
+              "name": "foo"
+            }
+          }
+        ],
+        "source": {
+          "type": "StringLiteral",
+          "start":16,"end":26,"loc":{"start":{"line":1,"column":16},"end":{"line":1,"column":26}},
+          "extra": {
+            "rawValue": "foo.json",
+            "raw": "\"foo.json\""
+          },
+          "value": "foo.json"
+        },
+        "assertions": [
+          {
+            "type": "ImportAttribute",
+            "start":36,"end":50,"loc":{"start":{"line":1,"column":36},"end":{"line":1,"column":50}},
+            "key": {
+              "type": "StringLiteral",
+              "start":36,"end":42,"loc":{"start":{"line":1,"column":36},"end":{"line":1,"column":42}},
+              "extra": {
+                "rawValue": "type",
+                "raw": "\"type\""
+              },
+              "value": "type"
+            },
+            "value": {
+              "type": "StringLiteral",
+              "start":44,"end":50,"loc":{"start":{"line":1,"column":44},"end":{"line":1,"column":50}},
+              "extra": {
+                "rawValue": "json",
+                "raw": "\"json\""
+              },
+              "value": "json"
+            }
+          },
+          {
+            "type": "ImportAttribute",
+            "start":52,"end":64,"loc":{"start":{"line":1,"column":52},"end":{"line":1,"column":64}},
+            "key": {
+              "type": "Identifier",
+              "start":52,"end":56,"loc":{"start":{"line":1,"column":52},"end":{"line":1,"column":56},"identifierName":"type"},
+              "name": "type"
+            },
+            "value": {
+              "type": "StringLiteral",
+              "start":58,"end":64,"loc":{"start":{"line":1,"column":58},"end":{"line":1,"column":64}},
+              "extra": {
+                "rawValue": "html",
+                "raw": "\"html\""
+              },
+              "value": "html"
+            }
+          },
+          {
+            "type": "ImportAttribute",
+            "start":66,"end":78,"loc":{"start":{"line":1,"column":66},"end":{"line":1,"column":78}},
+            "key": {
+              "type": "StringLiteral",
+              "start":66,"end":72,"loc":{"start":{"line":1,"column":66},"end":{"line":1,"column":72}},
+              "extra": {
+                "rawValue": "type",
+                "raw": "\"type\""
+              },
+              "value": "type"
+            },
+            "value": {
+              "type": "StringLiteral",
+              "start":74,"end":78,"loc":{"start":{"line":1,"column":74},"end":{"line":1,"column":78}},
+              "extra": {
+                "rawValue": "js",
+                "raw": "\"js\""
+              },
+              "value": "js"
+            }
+          }
+        ]
+      }
+    ],
+    "directives": []
+  }
+}

packages/babel-parser/test/fixtures/experimental/import-assertions/valid-string-assertion-key/input.js

@@ -0,0 +1 @@
+import "foo" assert { "type": "json" };

packages/babel-parser/test/fixtures/experimental/import-assertions/valid-string-assertion-key/output.json

@@ -0,0 +1,51 @@
+{
+  "type": "File",
+  "start":0,"end":39,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":39}},
+  "program": {
+    "type": "Program",
+    "start":0,"end":39,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":39}},
+    "sourceType": "module",
+    "interpreter": null,
+    "body": [
+      {
+        "type": "ImportDeclaration",
+        "start":0,"end":39,"loc":{"start":{"line":1,"column":0},"end":{"line":1,"column":39}},
+        "specifiers": [],
+        "source": {
+          "type": "StringLiteral",
+          "start":7,"end":12,"loc":{"start":{"line":1,"column":7},"end":{"line":1,"column":12}},
+          "extra": {
+            "rawValue": "foo",
+            "raw": "\"foo\""
+          },
+          "value": "foo"
+        },
+        "assertions": [
+          {
+            "type": "ImportAttribute",
+            "start":22,"end":36,"loc":{"start":{"line":1,"column":22},"end":{"line":1,"column":36}},
+            "key": {
+              "type": "StringLiteral",
+              "start":22,"end":28,"loc":{"start":{"line":1,"column":22},"end":{"line":1,"column":28}},
+              "extra": {
+                "rawValue": "type",
+                "raw": "\"type\""
+              },
+              "value": "type"
+            },
+            "value": {
+              "type": "StringLiteral",
+              "start":30,"end":36,"loc":{"start":{"line":1,"column":30},"end":{"line":1,"column":36}},
+              "extra": {
+                "rawValue": "json",
+                "raw": "\"json\""
+              },
+              "value": "json"
+            }
+          }
+        ]
+      }
+    ],
+    "directives": []
+  }
+}