Add ability to test errors (#8025)

tests/errors/graphql/__snapshots__/jsfmt.spec.js.snap

@@ -0,0 +1,12 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`type-interfaces.graphql error test 1`] = `
+"Syntax Error: Unexpected \\"|\\". (5:21)
+  3 | # which will break seperator detection added in #7305
+  4 | 
+> 5 | type A implements A | B {
+    |                     ^
+  6 |   a: a
+  7 | }
+  8 | "
+`;

tests/errors/graphql/jsfmt.spec.js

@@ -0,0 +1 @@
+run_spec(__dirname, ["graphql"]);

tests/errors/graphql/type-interfaces.graphql

@@ -0,0 +1,7 @@
+# This test to grantee `graphql` parser won't allow
+# something like `|` as seperator
+# which will break seperator detection added in #7305
+
+type A implements A | B {
+  a: a
+}

tests/errors/js/__snapshots__/jsfmt.spec.js.snap

@@ -0,0 +1,21 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`partial-template-strings.js error test 1`] = `
+"Unexpected token (6:42)
+  4 | 
+  5 | const Diagnostics = {
+> 6 |   unexpected_token: \`Unexpected token: \${?}\`,
+    |                                          ^
+  7 |   name_not_found: \`'\${?}' not found.\`
+  8 | };
+  9 | Diagnostics.name_not_found(\\"foo\\"); // \\"'foo' not found.\\""
+`;
+
+exports[`static-import-source-should-not-has-extra-token.js error test 1`] = `
+"Unexpected token (4:16)
+  2 | // be parenthesized, that accidentally break #8016
+  3 | 
+> 4 | import {} from (('a'));
+    |                ^
+  5 | "
+`;

tests/errors/js/jsfmt.spec.js

@@ -0,0 +1 @@
+run_spec(__dirname, ["babel"]);

tests/errors/js/partial-template-strings.js

@@ -0,0 +1,9 @@
+// partial template strings is not supported by babel yet
+// If parsers supported, should remove this and open a issue about this
+// Proposal: https://github.com/tc39/proposal-partial-application/blob/master/README.md#proposal
+
+const Diagnostics = {
+  unexpected_token: `Unexpected token: ${?}`,
+  name_not_found: `'${?}' not found.`
+};
+Diagnostics.name_not_found("foo"); // "'foo' not found."

tests/errors/js/static-import-source-should-not-has-extra-token.js

@@ -0,0 +1,4 @@
+// This test to grantee parsers won't allow static import source to
+// be parenthesized, that accidentally break #8016
+
+import {} from (('a'));

tests_config/run_spec.js

@@ -46,9 +46,21 @@ const unstableTests = new Map(
   })
 );
 
+const isTestDirectory = (dirname, name) =>
+  dirname.startsWith(path.join(__dirname, "../tests", name));
+
 global.run_spec = (dirname, parsers, options) => {
   // `IS_PARSER_INFERENCE_TESTS` mean to test `inferParser` on `standalone`
-  const IS_PARSER_INFERENCE_TESTS = dirname.endsWith("parser-inference");
+  const IS_PARSER_INFERENCE_TESTS = isTestDirectory(
+    dirname,
+    "parser-inference"
+  );
+
+  // `IS_ERROR_TESTS` mean to watch errors like:
+  // - syntax parser hasn't supported yet
+  // - syntax errors that should throws
+  const IS_ERROR_TESTS = isTestDirectory(dirname, "errors");
+
   if (IS_PARSER_INFERENCE_TESTS) {
     parsers = [];
   } else if (!parsers || !parsers.length) {
@@ -105,6 +117,16 @@ global.run_spec = (dirname, parsers, options) => {
       };
 
       const hasEndOfLine = "endOfLine" in mainOptions;
+
+      if (IS_ERROR_TESTS) {
+        test("error test", () => {
+          expect(() => {
+            format(input, filename, mainOptions);
+          }).toThrowErrorMatchingSnapshot();
+        });
+        return;
+      }
+
       const output = format(input, filename, mainOptions);
       const visualizedOutput = visualizeEndOfLine(output);