feat(json): log the filename when JSON.parse fails

Helpful when debugging Sometimes in a large codebase, a single comma buried in a gigantic json file can halt the entire build. This change ensures that users will more easily be able to find and fix those errors.
rollup · May 26, 2020 · 78db740 · 78db740
1 parent 867c699
commit 78db740
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Showing 3 changed files with 18 additions and 12 deletions.
diff --git a/README.md b/README.md
@@ -18,14 +18,14 @@ This repository houses plugins that Rollup considers critical to every day use o
 |                                       |                                                                                           |
 | ------------------------------------- | ----------------------------------------------------------------------------------------- |
 | [alias](packages/alias)               | Define and resolve aliases for bundle dependencies                                        |
-| [auto-install](packages/auto-install) | Automatically install dependencies that are imported by a bundle                         |
+| [auto-install](packages/auto-install) | Automatically install dependencies that are imported by a bundle                          |
 | [babel](packages/babel)               | Compile your files with Babel                                                             |
 | [beep](packages/beep)                 | System beeps on errors and warnings                                                       |
 | [buble](packages/buble)               | Compile ES2015 with buble                                                                 |
 | [commonjs](packages/commonjs)         | Convert CommonJS modules to ES6                                                           |
 | [data-uri](packages/data-uri)         | Import modules from Data URIs                                                             |
 | [dsv](packages/dsv)                   | Convert .csv and .tsv files into JavaScript modules with d3-dsv                           |
-| [html](packages/html)                 | Create HTML files to serve Rollup bundles                                                |
+| [html](packages/html)                 | Create HTML files to serve Rollup bundles                                                 |
 | [image](packages/image)               | Import JPG, PNG, GIF, SVG, and WebP files                                                 |
 | [inject](packages/inject)             | Scan modules for global variables and injects `import` statements where necessary         |
 | [json](packages/json)                 | Convert .json files to ES6 modules                                                        |

diff --git a/packages/json/src/index.js b/packages/json/src/index.js
@@ -11,15 +11,21 @@ export default function json(options = {}) {
     transform(json, id) {
       if (id.slice(-5) !== '.json' || !filter(id)) return null;
 
-      return {
-        code: dataToEsm(JSON.parse(json), {
-          preferConst: options.preferConst,
-          compact: options.compact,
-          namedExports: options.namedExports,
-          indent
-        }),
-        map: { mappings: '' }
-      };
+      try {
+        return {
+          code: dataToEsm(JSON.parse(json), {
+            preferConst: options.preferConst,
+            compact: options.compact,
+            namedExports: options.namedExports,
+            indent
+          }),
+          map: { mappings: '' }
+        };
+      } catch (err) {
+        const error = new Error(`Could not parse ${id}`);
+        error.originalError = err;
+        throw error;
+      }
     }
   };
 }
diff --git a/packages/json/test/test.js b/packages/json/test/test.js
@@ -80,7 +80,7 @@ test('handles garbage', async (t) => {
     });
 
   const error = await t.throwsAsync(bundle);
-  t.is(error.message.indexOf('Unexpected token o'), 0);
+  t.regex(error.message, /Could not parse (.*)\/fixtures\/garbage\/bad.json$/);
 });
 
 test('does not generate an AST', async (t) => {