feat(cov): add prerequire option (#53)

README.md

@@ -152,6 +152,7 @@ Coverage reporter will output text-summary, json and lcov.
 You can pass any mocha argv.
 
 - `-x` add dir ignore coverage, support multiple argv
+- `--prerequire` prerequire files for coverage instrument, you can use this options if load files slowly when call `mm.app` or `mm.cluster`
 - also support all test params above.
 
 #### environment

lib/cmd/cov.js

@@ -21,6 +21,10 @@ class CovCommand extends Command {
         description: 'istanbul coverage ignore, one or more fileset patterns',
         type: 'string',
       },
+      prerequire: {
+        description: 'prerequire files for coverage instrument',
+        type: 'boolean',
+      },
     };
 
     // you can add ignore dirs here
@@ -48,6 +52,10 @@ class CovCommand extends Command {
     process.env.NODE_ENV = 'test';
     process.env.TMPDIR = tmpDir;
 
+    if (argv.prerequire) {
+      process.env.EGG_BIN_PREREQUIRE = 'true';
+    }
+
     // istanbul coverage ignore
     if (argv.x) {
       this[EXCLUDES].add(argv.x);

test/fixtures/prerequire/test/index.test.js

@@ -0,0 +1,3 @@
+'use strict';
+
+console.log('EGG_BIN_PREREQUIRE', process.env.EGG_BIN_PREREQUIRE);

test/lib/cmd/cov.test.js

@@ -114,6 +114,23 @@ describe('test/lib/cmd/cov.test.js', () => {
           .expect('code', 1)
           .end(done);
       });
+
+      it('should set EGG_BIN_PREREQUIRE', function* () {
+        const cwd = path.join(__dirname, '../../fixtures/prerequire');
+        yield coffee.fork(eggBin, [ 'cov' ], { cwd })
+          .debug()
+          .coverage(false)
+          .expect('stdout', /EGG_BIN_PREREQUIRE undefined/)
+          .expect('code', 0)
+          .end();
+
+        yield coffee.fork(eggBin, [ 'cov', '--prerequire' ], { cwd })
+          .debug()
+          .coverage(false)
+          .expect('stdout', /EGG_BIN_PREREQUIRE true/)
+          .expect('code', 0)
+          .end();
+      });
     });
   } else {
     it('should exec test instead of cov in win32', done => {