melange/lookingGlass: better object inspection

Reworks object parsing code so that we can inspect more types,
present the information more clearly, and prevent misbehavior
with types we shouldn't iterate like importers.

Notable behavior changes:
 - Boxed instance proxies such as Clutter.Color, Clutter.Rect, etc
   are now inspectable like other objects.

 - Inspecting importers no longer loads every file.

 - Errors during command eval() are now inspectable.

 - Values are currently truncated at 120 characters. When an
   inspectable object's toString value is longer you will need
   to manually call toString() on it to view the full value.
   Strings are viewable in a popup dialog.

 - The 'shortValue' key in the Inspect dbus method is no longer
   used as it is not available on all of the methods, and so
   easier to deal shortening values on the Melange side.

Author: itzexor

files/usr/share/cinnamon/cinnamon-looking-glass/page_inspect.py

@@ -54,8 +54,13 @@ def onRowActivated(self, treeview, path, view_column):
 
     def setInspectionData(self, path, data):
         self.store.clear()
+        data.sort(key=lambda item: item["name"])
         for item in data:
-            self.store.append([item["name"], item["type"], item["shortValue"], item["value"], path + "['" + item["name"] + "']"])
+            self.store.append([item["name"],
+                               item["type"],
+                               pageutils.shortenValue(item["value"]),
+                               item["value"],
+                               path + "['" + item["name"] + "']"])
 
 class ModulePage(pageutils.WindowAndActionBars):
     def __init__(self, parent):
@@ -124,7 +129,7 @@ def pushInspectionElement(self):
             self.insert.set_sensitive(True)
 
     def updateInspector(self, path, objType, name, value, pushToStack=False):
-        if objType == "object":
+        if objType in ["array", "object"]:
             if pushToStack:
                 self.pushInspectionElement()
 
@@ -144,8 +149,8 @@ def updateInspector(self, path, objType, name, value, pushToStack=False):
                     self.view.store.clear()
             else:
                 self.view.store.clear()
-        elif objType == "undefined":
-            pageutils.ResultTextDialog("Value for '" + name + "'", "Value is <undefined>")
+        elif objType == "undefined" or objType == "null":
+            pageutils.ResultTextDialog("Value for '" + name + "'", "Value is <" + objType + ">")
         else:
             pageutils.ResultTextDialog("Value for " + objType + " '" + name + "'", value)
 

files/usr/share/cinnamon/cinnamon-looking-glass/page_results.py

@@ -5,7 +5,7 @@
 
 class ModulePage(pageutils.BaseListView):
     def __init__(self, parent):
-        store = Gtk.ListStore(int, str, str, str, str)
+        store = Gtk.ListStore(int, str, str, str, str, str)
         pageutils.BaseListView.__init__(self, store)
 
         self.parent = parent
@@ -41,7 +41,7 @@ def onRowActivated(self, treeview, path, view_column):
         resultId = self.store.get_value(treeIter, 0)
         name = self.store.get_value(treeIter, 1)
         objType = self.store.get_value(treeIter, 2)
-        value = self.store.get_value(treeIter, 3)
+        value = self.store.get_value(treeIter, 5)
 
         melangeApp.pages["inspect"].inspectElement("r(%d)" % resultId, objType, name, value)
 
@@ -55,7 +55,12 @@ def getUpdates(self):
         if success:
             try:
                 for item in data:
-                    self.store.append([int(item["index"]), item["command"], item["type"], item["object"], item["tooltip"]])
+                    self.store.append([int(item["index"]),
+                                      item["command"],
+                                      item["type"],
+                                      pageutils.shortenValue(item["object"]),
+                                      item["tooltip"],
+                                      item["object"]])
                 self._changed = True
                 self.parent.activatePage("results")
             except Exception as e:

files/usr/share/cinnamon/cinnamon-looking-glass/pageutils.py

@@ -2,6 +2,23 @@
 
 from gi.repository import Gtk
 
+# truncate a string to single line 121 char max with ellipsis
+def shortenValue(value):
+    changed = False
+    truncPos = value.find("\n")
+    if truncPos > 0:
+        changed = True
+        value = value[:truncPos]
+
+    if len(value) > 120:
+        changed = True
+        value = value[:120]
+
+    if changed:
+        value += "…"
+
+    return value
+
 class ResultTextDialog(Gtk.Dialog):
     def __init__(self, title, text):
         Gtk.Dialog.__init__(self, title, None, 0,

js/ui/lookingGlass.js

@@ -5,6 +5,7 @@ const Clutter = imports.gi.Clutter;
 const Cogl = imports.gi.Cogl;
 const Gio = imports.gi.Gio;
 const GLib = imports.gi.GLib;
+const GObject = imports.gi.GObject;
 const Lang = imports.lang;
 const Meta = imports.gi.Meta;
 const Signals = imports.signals;
@@ -36,13 +37,94 @@ var commandHeader = 'const Clutter = imports.gi.Clutter; ' +
                     'const r = Lang.bind(Main.lookingGlass, Main.lookingGlass.getResult); ';
 
 const HISTORY_KEY = 'looking-glass-history';
-function objectToString(o) {
-    if (typeof(o) == typeof(objectToString)) {
-        // special case this since the default is way, way too verbose
-        return '<js function>';
+
+/* fake types for special cases:
+ *  -"array": objects that pass Array.isArray() and should only show enumerable properties
+ *  -"importer": objects that load modules on property access
+ */
+
+// returns [typeString, valueString] for any object
+function getObjInfo(o) {
+    let type, value;
+    if (o === null)
+        type = "null";
+    else if (o === undefined)
+        type = "undefined";
+
+    if (type) {
+        value = "[" + type + "]";
     } else {
-        return '' + o;
+        // try to detect importers via their string representation
+        try {
+            value = o.toString();
+        } catch (e) {
+            if (e.message.includes("not an object instance - cannot convert to GObject*")) {
+                // work around Clutter.Actor.prototype.toString override not handling being
+                // called with the prototype itself as 'this'
+                value = GObject.Object.prototype.toString.call(o);
+            } else {
+                value = "[error getting value]";
+            }
+        }
+
+        if (value.startsWith("[GjsFileImporter")
+            || value.startsWith("[object GjsModule gi")) {
+            type = "importer";
+        } else if (Array.isArray(o)) {
+            type = "array";
+        } else {
+            type = typeof(o);
+        }
+
+        // make empty strings/arrays obvious
+        if (value === "")
+            value = "[empty]";
+    }
+
+    return [type, value];
+}
+
+// returns an array of dictionaries conforming to the Inspect dbus schema
+function getObjKeysInfo(obj) {
+    let [type, ] = getObjInfo(obj);
+    if (!["array", "object"].includes(type))
+        return [];
+
+    let keys = new Set();
+    let curProto = obj;
+
+    // we ignore the Object prototype
+    while (curProto && curProto !== Object.prototype) {
+        let ownKeys;
+        if (type === "array")
+            ownKeys = curProto.keys(); // index properties only
+        else
+            ownKeys = Reflect.ownKeys(curProto); // all own properties and symbols
+
+        // adding to set ignores duplicates
+        for (let key of ownKeys)
+            keys.add(key);
+
+        curProto = Object.getPrototypeOf(curProto);
+    }
+
+
+    return Array.from(keys).map((k) => {
+        let [t, v] = getObjInfo(obj[k]);
+        return { name: k.toString(), type: t, value: v, shortValue: "" };
+    });
+}
+
+// always returns an object we can give back to melange.
+// it may be useful to inspect Error() objects
+function tryEval(js) {
+    let out;
+    try {
+        out = eval(js);
+    } catch (e) {
+        out = e;
     }
+    return out;
 }
 
 function WindowList() {
@@ -93,13 +175,13 @@ WindowList.prototype = {
 
             let lgInfo = {
                 id: metaWindow._lgId.toString(),
-                title: objectToString(metaWindow.title),
-                wmclass: objectToString(metaWindow.get_wm_class()),
+                title: metaWindow.title + '',
+                wmclass: metaWindow.get_wm_class() + '',
                 app: '' };
 
             let app = tracker.get_window_app(metaWindow);
             if (app != null && !app.is_window_backed()) {
-                lgInfo.app = objectToString(app.get_id());
+                lgInfo.app = app.get_id() + '';
             } else {
                 lgInfo.app = '<untracked>';
             }
@@ -454,43 +536,18 @@ Melange.prototype = {
     _pushResult: function(command, obj, tooltip) {
         let index = this._results.length;
         let result = {"o": obj, "index": index};
-        this.rawResults.push({command: command, type: typeof(obj), object: objectToString(obj), index: index.toString(), tooltip: tooltip});
+        let [type, value] = getObjInfo(obj);
+        this.rawResults.push({command: command, type: type, object: value, index: index.toString(), tooltip: tooltip});
         this.emitResultUpdate();
-
+        
         this._results.push(result);
         this._it = obj;
     },
 
     inspect: function(path) {
         let fullCmd = commandHeader + path;
-
-        let result = eval(fullCmd);
-        let resultObj = [];
-        for (let key in result) {
-            let type = typeof(result[key]);
-
-            //fixme: move this shortvalue stuff to python lg
-            let shortValue, value;
-            if (type === "undefined") {
-                value = "";
-                shortValue = "";
-            } else if (result[key] === null) {
-                value = "[null]";
-                shortValue = value;
-            } else {
-                value = result[key].toString();
-                shortValue = value;
-                let i = value.indexOf('\n');
-                let j = value.indexOf('\r');
-                if (j != -1 && (i == -1 || i > j))
-                    i = j;
-                if (i != -1)
-                    shortValue = value.substr(0, i) + '.. <more>';
-            }
-            resultObj.push({ name: key, type: type, value: value, shortValue: shortValue});
-        }
-
-        return resultObj;
+        let result = tryEval(fullCmd);
+        return getObjKeysInfo(result);
     },
 
     getIt: function () {
@@ -519,24 +576,14 @@ Melange.prototype = {
         this._history.addItem(command);
 
         let fullCmd = commandHeader + command;
-
-        let resultObj;
-
         let ts = GLib.get_monotonic_time();
 
-        try {
-            resultObj = eval(fullCmd);
-        } catch (e) {
-            resultObj = '<exception ' + e + '>';
-        }
+        let resultObj = tryEval(fullCmd);
 
         let ts2 = GLib.get_monotonic_time();
-
         let tooltip = _("Execution time (ms): ") + (ts2 - ts) / 1000;
 
         this._pushResult(command, resultObj, tooltip);
-
-        return;
     },
 
     // DBus function
@@ -547,14 +594,7 @@ Melange.prototype = {
     // DBus function
     AddResult: function(path) {
         let fullCmd = commandHeader + path;
-
-        let resultObj;
-        try {
-            resultObj = eval(fullCmd);
-        } catch (e) {
-            resultObj = '<exception ' + e + '>';
-        }
-        this._pushResult(path, resultObj, "");
+        this._pushResult(path, tryEval(fullCmd), "");
     },
 
     // DBus function