[diff] Draw highlighters above gutters. Step 5: fix line render for soft-wrapped inline fragments

PROBLEM:
inline fragment can appear on 2 visible soft-wrapped lines (in case of short diff, for example), but we draw them only on one.

SOLUTION:
Make DiffLineMarkerRenderer calculate the real visual height of the modified range and draw the rectangle with correct height.

platform/platform-impl/src/com/intellij/openapi/diff/impl/DiffLineMarkerRenderer.java

@@ -20,8 +20,10 @@ import com.intellij.openapi.editor.Editor;
 import com.intellij.openapi.editor.ex.EditorEx;
 import com.intellij.openapi.editor.ex.EditorGutterComponentEx;
 import com.intellij.openapi.editor.markup.LineMarkerRenderer;
+import com.intellij.openapi.util.TextRange;
 import com.intellij.util.ui.UIUtil;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.awt.*;
 
@@ -30,18 +32,29 @@ import java.awt.*;
  * <p>Has ability to draw applied changes (used in the merge tool).</p>
  */
 public class DiffLineMarkerRenderer implements LineMarkerRenderer {
-  private final TextDiffType myDiffType;
-  private final boolean myEnsureAtLeastOneLineHigh;
+
+  @NotNull private final TextDiffType myDiffType;
+  @Nullable private final TextRange myTextRange;
+
+  @NotNull
+  public static DiffLineMarkerRenderer createStandardInstance(@NotNull TextDiffType diffType) {
+    return new DiffLineMarkerRenderer(diffType, null);
+  }
 
   /**
-   * @param diffType                 the type of the difference.
-   * @param ensureAtLeastOneLineHigh if true, the height of the rectangle will be at least one line high,
-   *                                 if 0 is passed as a height of the Rectangle to {@link #paint(Editor, Graphics, Rectangle)}.
-   *                                 The height won't be modified if ensureAtLeastOneLineHigh is false, or if height is not 0.
+   * Creates an instance of the renderer that calculates the visual height of the text range and ensures that the drawn rectangle is at
+   * least as high as needed.
+   * @param diffType the type of the difference.
+   * @param range    the highlighted text range.
    */
-  public DiffLineMarkerRenderer(@NotNull TextDiffType diffType, boolean ensureAtLeastOneLineHigh) {
+  @NotNull
+  public static DiffLineMarkerRenderer createHeightAdjustingInstance(@NotNull TextDiffType diffType, @NotNull TextRange range) {
+    return new DiffLineMarkerRenderer(diffType, range);
+  }
+
+  private DiffLineMarkerRenderer(@NotNull TextDiffType diffType, @Nullable TextRange range) {
     myDiffType = diffType;
-    myEnsureAtLeastOneLineHigh = ensureAtLeastOneLineHigh;
+    myTextRange = range;
   }
 
   @Override
@@ -58,8 +71,8 @@ public class DiffLineMarkerRenderer implements LineMarkerRenderer {
     int width = gutter.getWidth();
     int height = range.height;
 
-    if (height == 0 && myEnsureAtLeastOneLineHigh) {
-      height = editor.getLineHeight();
+    if (myTextRange != null) {
+      height = calcHeightInVisualLines(editor, myTextRange) * editor.getLineHeight();
     }
 
     if (!myDiffType.isApplied()) {
@@ -77,4 +90,18 @@ public class DiffLineMarkerRenderer implements LineMarkerRenderer {
       DiffUtil.drawBoldDottedFramingLines(g2, x, x + width, y - 1, y + height - 1, color);
     }
   }
+
+  private static int calcHeightInVisualLines(@NotNull Editor editor, @NotNull TextRange range) {
+    int startY = editor.offsetToVisualPosition(range.getStartOffset()).getLine();
+    int endY = editor.offsetToVisualPosition(range.getEndOffset()).getLine();
+    if (startY > endY) {
+      return 0;
+    }
+    return endY - startY + 1;
+  }
+
+  @NotNull
+  public TextDiffType getType() {
+    return myDiffType;
+  }
 }

platform/platform-impl/src/com/intellij/openapi/diff/impl/highlighting/DiffMarkup.java

@@ -95,8 +95,10 @@ public abstract class DiffMarkup implements EditorSource, Disposable {
       rangeMarker.setGutterIconRenderer(gutterIconRenderer);
     }
 
-    boolean ensureAtLeastOneLineHigh = shouldIncreaseHighlightingHeight(fragment, editor, range);
-    rangeMarker.setLineMarkerRenderer(new DiffLineMarkerRenderer(type, ensureAtLeastOneLineHigh));
+    boolean adjustHeight = shouldIncreaseHighlightingHeight(fragment, editor, range);
+    rangeMarker.setLineMarkerRenderer(adjustHeight
+                                      ? DiffLineMarkerRenderer.createHeightAdjustingInstance(type, range)
+                                      : DiffLineMarkerRenderer.createStandardInstance(type));
 
     Color stripeBarColor = attributes.getErrorStripeColor();
     if (stripeBarColor != null) {

platform/platform-impl/src/com/intellij/openapi/diff/impl/incrementalMerge/ChangeHighlighterHolder.java

@@ -78,7 +78,7 @@ class ChangeHighlighterHolder {
     RangeHighlighter highlighter = getMarkupModel().addLineHighlighter(line, layer, null);
     highlighter.setLineSeparatorColor(diffType.getTextBackground(myEditor));
     highlighterCreated(highlighter, diffType.getTextAttributes(myEditor), applied);
-    highlighter.setLineMarkerRenderer(new DiffLineMarkerRenderer(diffType, false));
+    highlighter.setLineMarkerRenderer(DiffLineMarkerRenderer.createStandardInstance(diffType));
     return highlighter;
   }
 
@@ -89,7 +89,7 @@ class ChangeHighlighterHolder {
     TextAttributes attributes = type.getTextAttributes(myEditor);
     RangeHighlighter highlighter = getMarkupModel().addRangeHighlighter(start, end, layer, attributes, targetArea);
     highlighterCreated(highlighter, attributes, applied);
-    highlighter.setLineMarkerRenderer(new DiffLineMarkerRenderer(type, false));
+    highlighter.setLineMarkerRenderer(DiffLineMarkerRenderer.createStandardInstance(type));
     return highlighter;
   }