feat: Named json output (#509)

Also fixes #485 by limiting output to a single file containing ALL compositions.

BREAKING CHANGE: The default file name when `json : true` has changed from whatever the CSS file was called to `exports.json`

docs/rollup.md

@@ -14,7 +14,7 @@ A minimatch pattern, or an array of minimatch patterns, relative to `process.cwd
 
 ### `json`
 
-Boolean to determine if JSON files should be output at the end of compilation. Defaults to `false`.
+Boolean/String to determine if JSON files containing all exported classes & values should be output. If set to `true` will write out to a file named `exports.json`. If a `String` will write out to that file name. Defaults to `false`.
 
 ### `map`
 

packages/rollup/README.md

@@ -54,7 +54,7 @@ A minimatch pattern, or an array of minimatch patterns, relative to `process.cwd
 
 ### `json`
 
-Boolean to determine if JSON files should be output at the end of compilation. Defaults to `false`.
+Boolean/String to determine if JSON files containing all exported classes & values should be output. If set to `true` will write out to a file named `exports.json`. If a `String` will write out to that file name. Defaults to `false`.
 
 ### `map`
 

packages/rollup/rollup.js

@@ -29,15 +29,11 @@ const makeFile = (details) => {
 
 module.exports = function(opts) {
     const options = Object.assign(Object.create(null), {
-        common : "common.css",
-
-        json : false,
-
-        include : "**/*.css",
-
+        common       : "common.css",
+        json         : false,
+        include      : "**/*.css",
         namedExports : true,
-
-        styleExport : false,
+        styleExport  : false,
     }, opts);
 
     const filter = utils.createFilter(options.include, options.exclude);
@@ -77,7 +73,7 @@ module.exports = function(opts) {
             }
 
             // Is this file being processed on a watch update?
-            if(runs && (id in processor.files)) {
+            if(runs++ && (id in processor.files)) {
                 const files = [];
 
                 // Watching will call transform w/ the same entry file, even if it
@@ -148,11 +144,6 @@ module.exports = function(opts) {
             };
         },
 
-        // Track # of runs since remove functionality needs to change
-        buildEnd() {
-            runs++;
-        },
-
         async generateBundle(outputOptions, bundles) {
             // styleExport disables all output file generation
             if(styleExport) {
@@ -248,7 +239,7 @@ module.exports = function(opts) {
             await Promise.all(
                 files
                 .filter(({ css }) => css.size)
-                .map(async ({ base, name, css }) => {
+                .map(async ({ base, name, css }, idx) => {
                     const id = this.emitAsset(`${base}.css`);
 
                     const result = await processor.output({
@@ -260,8 +251,12 @@ module.exports = function(opts) {
 
                     this.setAssetSource(id, result.css);
 
-                    if(options.json) {
-                        this.emitAsset(`${base}.json`, JSON.stringify(result.compositions, null, 4));
+                    // result.compositions always includes all the info, so it
+                    // doesn't actually matter which result we use. First one seems reasonable!
+                    if(options.json && idx === 0) {
+                        const file = typeof options.json === "string" ? options.json : "exports.json";
+
+                        this.emitAsset(file, JSON.stringify(result.compositions, null, 4));
                     }
 
                     if(result.map) {

packages/rollup/test/__snapshots__/rollup.test.js.snap

@@ -54,6 +54,15 @@ exports[`/rollup.js should generate JSON 1`] = `
 }"
 `;
 
+exports[`/rollup.js should generate JSON with a custom name 1`] = `
+"{
+    \\"packages/rollup/test/specimens/simple.css\\": {
+        \\"str\\": \\"\\\\\\"string\\\\\\"\\",
+        \\"fooga\\": \\"fooga\\"
+    }
+}"
+`;
+
 exports[`/rollup.js should generate exports 1`] = `
 "var css = {
     \\"str\\": \\"\\\\\\"string\\\\\\"\\",

packages/rollup/test/__snapshots__/splitting.test.js.snap

@@ -1,5 +1,39 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`/rollup.js code splitting should ouput only 1 JSON file 1`] = `
+Array [
+  Object {
+    "file": "common.css",
+    "text": "/* packages/rollup/test/specimens/simple.css */
+.fooga {
+    color: red;
+}
+",
+  },
+  Object {
+    "file": "dependencies.css",
+    "text": "/* packages/rollup/test/specimens/dependencies.css */
+.wooga {
+
+    background: blue;
+}
+",
+  },
+  Object {
+    "file": "exports.json",
+    "text": "{
+    \\"packages/rollup/test/specimens/dependencies.css\\": {
+        \\"wooga\\": \\"fooga wooga\\"
+    },
+    \\"packages/rollup/test/specimens/simple.css\\": {
+        \\"str\\": \\"\\\\\\"string\\\\\\"\\",
+        \\"fooga\\": \\"fooga\\"
+    }
+}",
+  },
+]
+`;
+
 exports[`/rollup.js code splitting should support dynamic imports 1`] = `
 Array [
   Object {

packages/rollup/test/rollup.test.js

@@ -160,7 +160,27 @@ describe("/rollup.js", () => {
             file : prefix(`./output/rollup/json/simple.js`),
         });
 
-        expect(read("./rollup/json/assets/simple.json")).toMatchSnapshot();
+        expect(read("./rollup/json/assets/exports.json")).toMatchSnapshot();
+    });
+
+    it("should generate JSON with a custom name", async () => {
+        const bundle = await rollup({
+            input   : require.resolve("./specimens/simple.js"),
+            plugins : [
+                plugin({
+                    namer,
+                    json : "custom.json",
+                }),
+            ],
+        });
+
+        await bundle.write({
+            format,
+            assetFileNames,
+            file : prefix(`./output/rollup/json-named/simple.js`),
+        });
+
+        expect(read("./rollup/json-named/assets/custom.json")).toMatchSnapshot();
     });
 
     it("should provide named exports", async () => {

packages/rollup/test/splitting.test.js

@@ -20,6 +20,8 @@ error.postcssPlugin = "error-plugin";
 const assetFileNames = "assets/[name][extname]";
 const format = "es";
 const map = false;
+const sourcemap = false;
+const json = true;
 
 describe("/rollup.js", () => {
     beforeAll(() => shell.rm("-rf", prefix("./output/rollup/*")));
@@ -47,6 +49,7 @@ describe("/rollup.js", () => {
 
             await bundle.write({
                 format,
+                sourcemap,
 
                 assetFileNames,
                 chunkFileNames,
@@ -76,6 +79,7 @@ describe("/rollup.js", () => {
 
             await bundle.write({
                 format,
+                sourcemap,
 
                 assetFileNames,
                 chunkFileNames,
@@ -105,6 +109,7 @@ describe("/rollup.js", () => {
 
             await bundle.write({
                 format,
+                sourcemap,
 
                 assetFileNames,
                 chunkFileNames,
@@ -140,6 +145,7 @@ describe("/rollup.js", () => {
 
             await bundle.write({
                 format,
+                sourcemap,
 
                 assetFileNames,
                 chunkFileNames,
@@ -171,6 +177,7 @@ describe("/rollup.js", () => {
 
             await bundle.write({
                 format,
+                sourcemap,
 
                 assetFileNames,
                 chunkFileNames,
@@ -180,5 +187,36 @@ describe("/rollup.js", () => {
 
             expect(dir("./rollup/dynamic-imports/assets/")).toMatchSnapshot();
         });
+
+        it("should ouput only 1 JSON file", async () => {
+            const bundle = await rollup({
+                experimentalCodeSplitting,
+
+                input : [
+                    require.resolve("./specimens/simple.js"),
+                    require.resolve("./specimens/dependencies.js"),
+                ],
+
+                plugins : [
+                    plugin({
+                        namer,
+                        map,
+                        json,
+                    }),
+                ],
+            });
+
+            await bundle.write({
+                format,
+                sourcemap,
+
+                assetFileNames,
+                chunkFileNames,
+
+                dir : prefix(`./output/rollup/json-splitting`),
+            });
+
+            expect(dir("./rollup/json-splitting/assets")).toMatchSnapshot();
+        });
     });
 });