Merge "SideBySide2: Defer syntax highlighting on large files"

Documentation/rest-api-changes.txt

@@ -2311,11 +2311,13 @@ As response a link:#diff-info[DiffInfo] entity is returned that describes the di
   {
     "meta_a": {
       "name": "gerrit-server/src/main/java/com/google/gerrit/server/project/RefControl.java",
-      "content_type": "text/x-java-source"
+      "content_type": "text/x-java-source",
+      "lines": 372
     },
     "meta_b": {
       "name": "gerrit-server/src/main/java/com/google/gerrit/server/project/RefControl.java",
-      "content_type": "text/x-java-source"
+      "content_type": "text/x-java-source",
+      "lines": 578
     },
     "change_type": "MODIFIED",
     "diff_header": [
@@ -2379,11 +2381,13 @@ If the `intraline` parameter is specified, intraline differences are included in
   {
     "meta_a": {
       "name": "gerrit-server/src/main/java/com/google/gerrit/server/project/RefControl.java",
-      "content_type": "text/x-java-source"
+      "content_type": "text/x-java-source",
+      "lines": 372
     },
     "meta_b": {
       "name": "gerrit-server/src/main/java/com/google/gerrit/server/project/RefControl.java",
-      "content_type": "text/x-java-source"
+      "content_type": "text/x-java-source",
+      "lines": 578
     },
     "change_type": "MODIFIED",
     "diff_header": [
@@ -2431,11 +2435,13 @@ be generated.
   {
     "meta_a": {
       "name": "gerrit-server/src/main/java/com/google/gerrit/server/project/RefControl.java",
-      "content_type": "text/x-java-source"
+      "content_type": "text/x-java-source",
+      "lines": 578
     },
     "meta_b": {
       "name": "gerrit-server/src/main/java/com/google/gerrit/server/project/RefControl.java",
-      "content_type": "text/x-java-source"
+      "content_type": "text/x-java-source",
+      "lines": 578
     },
     "change_type": "MODIFIED",
     "content": [
@@ -3008,6 +3014,7 @@ The `DiffFileMetaInfo` entity contains meta information about a file diff.
 |Field Name    |Description
 |`name`        |The name of the file.
 |`content_type`|The content type of the file.
+|`lines`       |The total number of lines in the file.
 |==========================
 
 [[diff-info]]

gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/DiffInfo.java

@@ -99,6 +99,7 @@ public class DiffInfo extends JavaScriptObject {
   public static class FileMeta extends JavaScriptObject {
     public final native String name() /*-{ return this.name; }-*/;
     public final native String content_type() /*-{ return this.content_type; }-*/;
+    public final native int lines() /*-{ return this.lines || 0 }-*/;
 
     protected FileMeta() {
     }

gerrit-gwtui/src/main/java/com/google/gerrit/client/diff/SideBySide2.java

@@ -49,6 +49,7 @@ import com.google.gwt.core.client.JavaScriptObject;
 import com.google.gwt.core.client.JsArray;
 import com.google.gwt.core.client.JsArrayString;
 import com.google.gwt.core.client.Scheduler;
+import com.google.gwt.core.client.Scheduler.RepeatingCommand;
 import com.google.gwt.core.client.Scheduler.ScheduledCommand;
 import com.google.gwt.dom.client.Element;
 import com.google.gwt.dom.client.NativeEvent;
@@ -122,6 +123,7 @@ public class SideBySide2 extends Screen {
   private JsArray<CommentInfo> draftsBase;
   private JsArray<CommentInfo> draftsRevision;
   private DiffInfo diff;
+  private boolean largeFile;
   private LineMapper mapper;
   private List<TextMarker> markers;
   private List<Runnable> undoLineClass;
@@ -188,10 +190,16 @@ public class SideBySide2 extends Screen {
         @Override
         public void onSuccess(DiffInfo diffInfo) {
           diff = diffInfo;
-          new ModeInjector()
-            .add(getContentType(diff.meta_a()))
-            .add(getContentType(diff.meta_b()))
-            .inject(modeInjectorCb);
+          if (prefs.syntaxHighlighting()) {
+            largeFile = isLargeFile(diffInfo);
+            if (largeFile) {
+              modeInjectorCb.onSuccess(null);
+            } else {
+              injectMode(diffInfo, modeInjectorCb);
+            }
+          } else {
+            modeInjectorCb.onSuccess(null);
+          }
         }
       }));
 
@@ -524,6 +532,18 @@ public class SideBySide2 extends Screen {
         resizeCodeMirror();
       }
     });
+
+    if (largeFile && prefs.syntaxHighlighting()) {
+      Scheduler.get().scheduleFixedDelay(new RepeatingCommand() {
+        @Override
+        public boolean execute() {
+          if (prefs.syntaxHighlighting() && isAttached()) {
+            setSyntaxHighlighting(prefs.syntaxHighlighting());
+          }
+          return false;
+        }
+      }, 250);
+    }
   }
 
   private CodeMirror createCodeMirror(
@@ -536,7 +556,7 @@ public class SideBySide2 extends Screen {
       .set("cursorHeight", 0.85)
       .set("lineNumbers", true)
       .set("tabSize", prefs.tabSize())
-      .set("mode", getContentType(meta))
+      .set("mode", largeFile ? null : getContentType(meta))
       .set("lineWrapping", false)
       .set("styleSelectedText", true)
       .set("showTrailingSpace", prefs.showWhitespaceErrors())
@@ -573,14 +593,26 @@ public class SideBySide2 extends Screen {
     prefsAction.update();
   }
 
-  void setSyntaxHighlighting(final boolean b) {
-    operation(new Runnable() {
+  void setSyntaxHighlighting(boolean b) {
+    if (b) {
+      injectMode(diff, new AsyncCallback<Void>() {
         @Override
-      public void run() {
-        cmA.setOption("mode", b ? getContentType(diff.meta_a()) : null);
-        cmB.setOption("mode", b ? getContentType(diff.meta_b()) : null);
+        public void onSuccess(Void result) {
+          if (prefs.syntaxHighlighting()) {
+            cmA.setOption("mode", getContentType(diff.meta_a()));
+            cmB.setOption("mode", getContentType(diff.meta_b()));
+          }
+        }
+
+        @Override
+        public void onFailure(Throwable caught) {
+          prefs.syntaxHighlighting(false);
         }
       });
+    } else {
+      cmA.setOption("mode", (String) null);
+      cmB.setOption("mode", (String) null);
+    }
   }
 
   void setContext(final int context) {
@@ -1547,6 +1579,13 @@ public class SideBySide2 extends Screen {
         : null;
   }
 
+  private void injectMode(DiffInfo diffInfo, AsyncCallback<Void> cb) {
+    new ModeInjector()
+      .add(getContentType(diffInfo.meta_a()))
+      .add(getContentType(diffInfo.meta_b()))
+      .inject(cb);
+  }
+
   DiffPreferences getPrefs() {
     return prefs;
   }
@@ -1624,4 +1663,9 @@ public class SideBySide2 extends Screen {
         }
       });
   }
+
+  private static boolean isLargeFile(DiffInfo diffInfo) {
+    return (diffInfo.meta_a() != null && diffInfo.meta_a().lines() > 500)
+        || (diffInfo.meta_b() != null && diffInfo.meta_b().lines() > 500);
+  }
 }

gerrit-server/src/main/java/com/google/gerrit/server/change/GetDiff.java

@@ -132,12 +132,14 @@ public class GetDiff implements RestReadView<FileResource> {
         result.metaA = new FileMeta();
         result.metaA.name = Objects.firstNonNull(ps.getOldName(), ps.getNewName());
         result.metaA.setContentType(ps.getFileModeA(), ps.getMimeTypeA());
+        result.metaA.lines = ps.getA().size();
       }
 
       if (ps.getDisplayMethodB() != DisplayMethod.NONE) {
         result.metaB = new FileMeta();
         result.metaB.name = ps.getNewName();
         result.metaB.setContentType(ps.getFileModeB(), ps.getMimeTypeB());
+        result.metaB.lines = ps.getB().size();
       }
 
       if (intraline) {
@@ -179,7 +181,7 @@ public class GetDiff implements RestReadView<FileResource> {
   static class FileMeta {
     String name;
     String contentType;
-    String url;
+    Integer lines;
 
     void setContentType(FileMode fileMode, String mimeType) {
       switch (fileMode) {