feat: cache now turned on by default (#454)

BREAKING CHANGE: nyc's cache is now enabled by default

Author: bcoe

index.js

@@ -1,5 +1,6 @@
 /* global __coverage__ */
 var arrify = require('arrify')
+var debugLog = require('debug-log')('nyc')
 var fs = require('fs')
 var glob = require('glob')
 var libCoverage = require('istanbul-lib-coverage')
@@ -270,7 +271,7 @@ NYC.prototype._transformFactory = function (cacheDir) {
       instrumented = instrumenter.instrumentSync(code, filename, sourceMap)
     } catch (e) {
       // don't fail external tests due to instrumentation bugs.
-      console.warn('failed to instrument', filename, 'with error:', e.stack)
+      debugLog('failed to instrument ' + filename + 'with error: ' + e.stack)
       instrumented = code
     }
 

lib/config-util.js

@@ -133,7 +133,7 @@ Config.buildYargs = function (cwd) {
     })
     .option('cache', {
       alias: 'c',
-      default: false,
+      default: true,
       type: 'boolean',
       describe: 'cache instrumentation results for improved performance'
     })

package.json

@@ -95,7 +95,7 @@
     "rimraf": "^2.5.4",
     "signal-exit": "^3.0.1",
     "spawn-wrap": "^1.2.4",
-    "test-exclude": "^3.2.2",
+    "test-exclude": "^3.3.0",
     "yargs": "^6.4.0",
     "yargs-parser": "^4.0.2"
   },
@@ -104,6 +104,7 @@
     "bundle-dependencies": "^1.0.2",
     "chai": "^3.0.0",
     "coveralls": "^2.11.11",
+    "debug-log": "^1.0.1",
     "exists-sync": "0.0.4",
     "forking-tap": "^0.1.1",
     "is-windows": "^0.2.0",
@@ -112,8 +113,8 @@
     "requirejs": "^2.3.0",
     "sanitize-filename": "^1.5.3",
     "sinon": "^1.15.3",
-    "split-lines": "^1.0.0",
     "source-map-support": "^0.4.6",
+    "split-lines": "^1.0.0",
     "standard": "^8.0.0",
     "standard-version": "^3.0.0",
     "tap": "^8.0.0",
@@ -157,4 +158,4 @@
       "find-up"
     ]
   }
-}
+}

test/src/nyc-bin.js

@@ -655,7 +655,7 @@ describe('the nyc cli', function () {
                 fs.readFileSync(file, 'utf-8')
               ))
             })
-            Object.keys(coverage)[0].should.equal('./external-instrumenter.js')
+            Object.keys(coverage).should.include('./external-instrumenter.js')
 
             // we should not have executed file, so all counts sould be 0.
             var sum = 0