[show-hint addon] Fix more race conditions

Clean up duplicated logic

Issue #3189

addon/hint/show-hint.js

@@ -24,44 +24,44 @@
     return cm.showHint(newOpts);
   };
 
-  var asyncRunID = 0;
-  function retrieveHints(getter, cm, options, then) {
-    if (getter.async) {
-      var id = ++asyncRunID;
-      getter(cm, function(hints) {
-        if (asyncRunID == id) then(hints);
-      }, options);
-    } else {
-      then(getter(cm, options));
-    }
-  }
-
   CodeMirror.defineExtension("showHint", function(options) {
     // We want a single cursor position.
     if (this.listSelections().length > 1 || this.somethingSelected()) return;
 
     if (this.state.completionActive) this.state.completionActive.close();
     var completion = this.state.completionActive = new Completion(this, options);
-    var getHints = completion.options.hint;
-    if (!getHints) return;
+    if (!completion.options.hint) return;
 
     CodeMirror.signal(this, "startCompletion", this);
-    return retrieveHints(getHints, this, completion.options, function(hints) { completion.showHints(hints); });
+    completion.update();
   });
 
   function Completion(cm, options) {
     this.cm = cm;
     this.options = this.buildOptions(options);
-    this.widget = this.onClose = null;
+    this.widget = null;
+    this.debounce = 0;
+    this.tick = 0;
+    this.startPos = this.cm.getCursor();
+    this.startLen = this.cm.getLine(this.startPos.line).length;
+
+    var self = this;
+    cm.on("cursorActivity", this.activityFunc = function() { self.cursorActivity(); });
   }
 
+  var requestAnimationFrame = window.requestAnimationFrame || function(fn) {
+    return setTimeout(fn, 1000/60);
+  };
+  var cancelAnimationFrame = window.cancelAnimationFrame || clearTimeout;
+
   Completion.prototype = {
     close: function() {
       if (!this.active()) return;
       this.cm.state.completionActive = null;
+      this.tick = null;
+      this.cm.off("cursorActivity", this.activityFunc);
 
       if (this.widget) this.widget.close();
-      if (this.onClose) this.onClose();
       CodeMirror.signal(this.cm, "endCompletion", this.cm);
     },
 
@@ -87,66 +87,51 @@
         this.showWidget(data);
     },
 
-    showWidget: function(data) {
-      this.widget = new Widget(this, data);
-      CodeMirror.signal(data, "shown");
-
-      var debounce = 0, completion = this, tick = 0;
-      var closeOn = this.options.closeCharacters;
-      var startPos = this.cm.getCursor(), startLen = this.cm.getLine(startPos.line).length;
-
-      var requestAnimationFrame = window.requestAnimationFrame || function(fn) {
-        return setTimeout(fn, 1000/60);
-      };
-      var cancelAnimationFrame = window.cancelAnimationFrame || clearTimeout;
-
-      function done() {
-        if (tick == null) return;
-        tick = null;
-        completion.close();
-        completion.cm.off("cursorActivity", activity);
-        if (data) CodeMirror.signal(data, "close");
+    cursorActivity: function() {
+      if (this.debounce) {
+        cancelAnimationFrame(this.debounce);
+        this.debounce = 0;
       }
 
-      function update(myTick) {
-        if (tick == null) return;
-        var myTick = ++tick;
-        if (data) CodeMirror.signal(data, "update");
-        retrieveHints(completion.options.hint, completion.cm, completion.options,
-                      function(d) { finishUpdate(d, myTick); });
-      }
-      function finishUpdate(data_, myTick) {
-        if (tick != myTick) return;
-        data = data_;
-        var picked = completion.widget && completion.widget.picked;
-        if (completion.widget) completion.widget.close();
-        if (data && data.list.length) {
-          if (picked && data.list.length == 1) completion.pick(data, 0);
-          else completion.widget = new Widget(completion, data);
-        }
+      var pos = this.cm.getCursor(), line = this.cm.getLine(pos.line);
+      if (pos.line != this.startPos.line || line.length - pos.ch != this.startLen - this.startPos.ch ||
+          pos.ch < this.startPos.ch || this.cm.somethingSelected() ||
+          (pos.ch && this.options.closeCharacters.test(line.charAt(pos.ch - 1)))) {
+        this.close();
+      } else {
+        var self = this;
+        this.debounce = requestAnimationFrame(function() {self.update();});
+        if (this.widget) this.widget.disable();
       }
+    },
 
-      function clearDebounce() {
-        if (debounce) {
-          cancelAnimationFrame(debounce);
-          debounce = 0;
-        }
+    update: function() {
+      if (this.tick == null) return;
+      if (this.data) CodeMirror.signal(this.data, "update");
+      if (!this.options.hint.async) {
+        this.finishUpdate(this.options.hint(this.cm, this.options), myTick);
+      } else {
+        var myTick = ++this.tick, self = this;
+        this.options.hint(this.cm, function(data) {
+          if (self.tick == myTick) self.finishUpdate(data);
+        }, this.options);
       }
+    },
 
-      function activity() {
-        clearDebounce();
-        var pos = completion.cm.getCursor(), line = completion.cm.getLine(pos.line);
-        if (pos.line != startPos.line || line.length - pos.ch != startLen - startPos.ch ||
-            pos.ch < startPos.ch || completion.cm.somethingSelected() ||
-            (pos.ch && closeOn.test(line.charAt(pos.ch - 1)))) {
-          completion.close();
-        } else {
-          debounce = requestAnimationFrame(update);
-          if (completion.widget) completion.widget.disable();
-        }
+    finishUpdate: function(data) {
+      this.data = data;
+      var picked = this.widget && this.widget.picked;
+      if (this.widget) this.widget.close();
+      if (data && data.list.length) {
+        if (picked && data.list.length == 1) this.pick(data, 0);
+        else this.widget = new Widget(this, data);
       }
-      this.cm.on("cursorActivity", activity);
-      this.onClose = done;
+    },
+
+    showWidget: function(data) {
+      this.data = data;
+      this.widget = new Widget(this, data);
+      CodeMirror.signal(data, "shown");
     },
 
     buildOptions: function(options) {