Rename coordsFromIndex to posFromIndex, add indexFromPos

Author: marijnh

lib/codemirror.js

@@ -250,7 +250,7 @@ var CodeMirror = (function() {
       moveV: operation(moveV),
       toggleOverwrite: function() {overwrite = !overwrite;},
 
-      coordsFromIndex: function(off) {
+      posFromIndex: function(off) {
         var lineNo = 0, ch;
         doc.iter(0, doc.size, function(line) {
           var sz = line.text.length + 1;
@@ -260,6 +260,14 @@ var CodeMirror = (function() {
         });
         return clipPos({line: lineNo, ch: ch});
       },
+      indexFromPos: function (coords) {
+        if (coords.line < 0 || coords.ch < 0) return 0;
+        var index = coords.ch;
+        doc.iter(0, coords.line, function (line) {
+          index += line.text.length + 1;
+        });
+        return index;
+      },
 
       operation: function(f){return operation(f)();},
       refresh: function(){updateDisplay(true);},

manual.html

@@ -569,12 +569,14 @@ <h2 id="api">Programming API</h2>
       objects. <code>to</code> can be left off to simply insert the
       string at position <code>from</code>.</dd>
 
-      <dt id="coordsFromIndex"><code>coordsFromIndex(index) → object</code></dt>
+      <dt id="posFromIndex"><code>posFromIndex(index) → object</code></dt>
       <dd>Calculates and returns a <code>{line, ch}</code> object for a
       zero-based <code>index</code> who's value is relative to the start of the
       editor's text. If the <code>index</code> is out of range of the text then
       the returned object is clipped to start or end of the text
       respectively.</dd>
+      <dt id="indexFromPos"><code>indexFromPos(object) → number</code></dt>
+      <dd>The reverse of <a href="#posFromIndex"><code>posFromIndex</code></a>.</dd>
     </dl>
 
     <p>The following are more low-level methods:</p>

test/test.js

@@ -94,7 +94,7 @@ test("defaults", function() {
     eq(defs.indentUnit, 5);
     eq(cm.getValue(), "uu");
     eq(cm.getOption("enterMode"), "keep");
-    eq(cm.getInputField().tabindex, 55);
+    eq(cm.getInputField().tabIndex, 55);
   }
   finally {
     CodeMirror.defaults = olddefaults;
@@ -147,7 +147,7 @@ testCM("coordsChar", function(cm) {
   }
 });
 
-testCM("coordsFromIndex", function(cm) {
+testCM("posFromIndex", function(cm) {
   cm.setValue(
     "This function should\n" +
     "convert a zero based index\n" +
@@ -166,9 +166,11 @@ testCM("coordsFromIndex", function(cm) {
 
   for (var i = 0; i < examples.length; i++) {
     var example = examples[i];
-    var pos = cm.coordsFromIndex(example.index);
+    var pos = cm.posFromIndex(example.index);
     eq(pos.line, example.line);
     eq(pos.ch, example.ch);
+    if (example.index >= 0 && example.index < 64)
+      eq(cm.indexFromPos(pos), example.index);
   }  
 });