Stream output from jake.exec, handle errors better.

mpareja · Feb 6, 2012 · dd01cf1 · dd01cf1
1 parent 8afc8ad
commit dd01cf1
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Showing 2 changed files with 83 additions and 35 deletions.
diff --git a/lib/api.js b/lib/api.js
@@ -62,12 +62,21 @@ var api = new (function () {
   };
 
   this.fail = function (err, code) {
+    var msg
+      , errObj;
     if (code) {
       jake.errorCode = code;
     }
     if (err) {
       if (typeof err == 'string') {
-        throw new Error(err);
+        // Use the initial or only line of the error as the error-message
+        // If there was a multi-line error, use the rest as the stack
+        msg = err.split('/n');
+        errObj = new Error(msg.shift());
+        if (msg.length) {
+          errObj.stack = msg.join('\n');
+        }
+        throw errObj;
       }
       else if (err instanceof Error) {
         throw err;

diff --git a/lib/utils.js b/lib/utils.js
@@ -18,9 +18,48 @@
 
 
 var exec = require('child_process').exec
+  , spawn = require('child_process').spawn
   , utils;
 
 utils = new (function () {
+  var _mix = function (targ, src, merge, includeProto) {
+        for (var p in src) {
+          // Don't copy stuff from the prototype
+          if (src.hasOwnProperty(p) || includeProto) {
+            if (merge &&
+                // Assumes the source property is an Object you can
+                // actually recurse down into
+                (typeof src[p] == 'object') &&
+                (src[p] !== null) &&
+                !(src[p] instanceof Array)) {
+              // Create the source property if it doesn't exist
+              // TODO: What if it's something weird like a String or Number?
+              if (typeof targ[p] == 'undefined') {
+                targ[p] = {};
+              }
+              _mix(targ[p], src[p], merge, includeProto); // Recurse
+            }
+            // If it's not a merge-copy, just set and forget
+            else {
+              targ[p] = src[p];
+            }
+          }
+        }
+      }
+
+    , _trim = function (s) {
+        var str = s || '';
+        return str.replace(/^\s*|\s*$/g, '');
+      }
+
+    , _truncate = function (s) {
+        var str = s || '';
+        if (str != '\n') {
+          str = str.replace(/\n$/, '')
+        }
+        return str;
+      };
+
 
   this.exec = function (arr, callback, opts) {
     var options = opts || {}
@@ -32,19 +71,44 @@ utils = new (function () {
       , run;
 
     run = function () {
-      var next = list.shift();
+      var sh
+        , cmd
+        , args
+        , next = list.shift()
+        , errData = '';
+      // Keep running as long as there are commands in the array
       if (next) {
-        exec(next, function (err, stdout, stderr) {
-          if (err && breakOnError) {
-            throw err;
+        // Split the command-name from the args passed to it
+        args = next.split(' ');
+        cmd = args.shift();
+        // Spawn a child-process, set up output
+        sh = spawn(cmd, args);
+        // Out
+        if (stdout) {
+          sh.stdout.on('data', function (data) {
+            console.log(_truncate(data.toString()));
+          });
+        }
+        // Err
+        sh.stderr.on('data', function (data) {
+          var d = data.toString();
+          if (stderr) {
+            console.log(_truncate(d));
           }
-          if (stderr && options.stderr) {
-            console.log('Error: ' + stderr);
+          // Accumulate the error-data so we can use it as the
+          // stack if the process exits with an error
+          errData += d;
+        });
+        // Exit, handle err or run next
+        sh.on('exit', function (code) {
+          var msg = errData || 'Process exited with error.';
+          msg = _trim(msg);
+          if (breakOnError && code != 0) {
+            fail(msg, code);
           }
-          if (stdout && options.stdout) {
-            console.log(stdout);
+          else {
+            run();
           }
-          run();
         });
       }
       else {
@@ -57,31 +121,6 @@ utils = new (function () {
     run();
   };
 
-  var _mix = function (targ, src, merge, includeProto) {
-    for (var p in src) {
-      // Don't copy stuff from the prototype
-      if (src.hasOwnProperty(p) || includeProto) {
-        if (merge &&
-            // Assumes the source property is an Object you can
-            // actually recurse down into
-            (typeof src[p] == 'object') &&
-            (src[p] !== null) &&
-            !(src[p] instanceof Array)) {
-          // Create the source property if it doesn't exist
-          // TODO: What if it's something weird like a String or Number?
-          if (typeof targ[p] == 'undefined') {
-            targ[p] = {};
-          }
-          _mix(targ[p], src[p], merge, includeProto); // Recurse
-        }
-        // If it's not a merge-copy, just set and forget
-        else {
-          targ[p] = src[p];
-        }
-      }
-    }
-  };
-
   this.objectToString = function (object) {
     var objectArray = [];
     for (var key in object) {