DSL for mapping

pgte · Sep 16, 2012 · dacad89 · dacad89
1 parent dc1a1f5
commit dacad89
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Showing 3 changed files with 99 additions and 16 deletions.
diff --git a/lib/map.js b/lib/map.js
@@ -1,4 +1,5 @@
 var Stream = require('stream').Stream;
+var BufferedStream = require('bufferedstream');
 
 var actions = ['remove', 'replace', 'update'];
 
@@ -11,12 +12,39 @@ function actionFromVal(val) {
     try {
       throw new Error('Ambiguous action, don\'t know what to do with' + JSON.stringify(val));
     } catch (e) {
-      throw new Error('Ambiguous action, don\'t know what to do with it');
+      throw new Error('Ambiguous action, don\'t know what to do with it:' + val.toString());
     }
   }
   return remainingActions[0];
 }
 
+function handleStream(selector, action, stream) {
+  var buffer = [], ended = false;
+  stream.on('data', function(d) { buffer.push(d); });
+  stream.on('end', function() { ended = true; });
+
+  this.select(selector, function(node) {
+    node[action](function(html) {
+      var index = 0;
+      var bs = new BufferedStream();
+
+      (function flush() {
+        if (buffer.length > index) {
+          bs.write(buffer[index]);
+          index ++;
+        }
+        if (buffer.length > index || ! ended) {
+          process.nextTick(flush);
+        } else {
+          bs.end();
+        }
+      }());
+
+      return bs;
+    });
+  });
+}
+
 function map(mapping) {
   var self = this;
 
@@ -27,34 +55,36 @@ function map(mapping) {
   Object.keys(mapping).forEach(function(selector) {
     var val = mapping[selector];
 
-    // console.log('val:', val);
-
     switch (typeof val) {
 
       case 'string':
       case 'function':
 
-        console.log('A');
-
-        console.log('.update(%j, %s)', selector, val);
-
         self.update(selector, val);
 
         break;
 
       case 'object':
 
-        console.log('B');
-
-        var action = actionFromVal(val);
-        if (! action) {
-          throw new Error('Value for selector `' + selector + '` should contain action field, either rmeove, replace or update');
+        if (val instanceof Stream) {
+
+          handleStream.call(self, selector, 'update', val);
+
+        } else {
+
+          var action = actionFromVal(val);
+          if (! action) {
+            throw new Error('Value for selector `' + selector +
+              '` should contain action field, either remove, replace or update');
+          }
+          var replaceBy = val[action];
+          if (replaceBy instanceof Stream) {
+            handleStream.call(self, selector, action, replaceBy);
+          } else {
+            self[action](selector, replaceBy);
+          }
         }
 
-        console.log('.%s(%j, %j)', action, selector, val[action]);
-
-        self[action](selector, val[action]);
-
         break;
 
       default:

diff --git a/lib/select.js b/lib/select.js
@@ -142,6 +142,14 @@ module.exports = function (parser, opts) {
             if (done) { done(); }
         });
     };
+
+    stream.pause = function() {
+        parser.pause();
+    };
+
+    stream.resume = function() {
+        parser.resume();
+    };
 
     return stream;
 };

diff --git a/test/dsl_compose_streaming.js b/test/dsl_compose_streaming.js
@@ -0,0 +1,45 @@
+var test = require('tap').test;
+var trumpet = require('../');
+var fs = require('fs');
+var BufferedStream = require('bufferedstream');
+
+test('compose with streams', function (t) {
+    t.plan(1);
+    var html = fs.readFileSync(__dirname + '/compose_target.html', 'utf8');
+
+    var tr = trumpet();
+    fs.createReadStream(__dirname + '/compose.html').pipe(tr);
+
+    var tr2 = trumpet();
+    fs.createReadStream(__dirname + '/partial.html').pipe(tr2);
+
+    var tr3 = trumpet();
+    fs.createReadStream(__dirname + '/partial.html').pipe(tr3);
+    tr3.select('.b span', function(node) {
+        node.update(function(html) {
+            return html.toUpperCase();
+        });
+    });
+
+    var stream = new BufferedStream();
+    stream.end('<b>NOTHING TO SEE HERE</b>');
+
+    var stream2 = new BufferedStream();
+    stream2.end('<blink>TERRIBLE</blink>');
+
+    tr.map({
+        '.b span': tr2,
+        '.c': tr3,
+        '.d': { remove: true },
+        '.e': { remove: true },
+        '.f': { replace: stream },
+        '.g': { replace: stream2}
+    });
+
+    var data = '';
+    tr.on('data', function (buf) { data += buf });
+
+    tr.on('end', function () {
+        t.equal(data, html);
+    });
+});