Bug 573223 - Improve chained array variable hoveringI20210621-1800

With this fix it adds array field hovering on local variables in static
frames which are chained.


Change-Id: I7073ab705470b3e6110dad4671287928210e8087
Signed-off-by: Gayan Perera <gayanper@gmail.com>
Reviewed-on: https://git.eclipse.org/r/c/jdt/eclipse.jdt.debug/+/182274
Tested-by: JDT Bot <jdt-bot@eclipse.org>
Reviewed-by: Sarika Sinha <sarika.sinha@in.ibm.com>

3 files changed, 117 insertions, 2 deletions

diff --git a/org.eclipse.jdt.debug.tests/java8/Bug572629.java b/org.eclipse.jdt.debug.tests/java8/Bug572629.java
index 84c5fb483..9fb653cfd 100644
--- a/org.eclipse.jdt.debug.tests/java8/Bug572629.java
+++ b/org.eclipse.jdt.debug.tests/java8/Bug572629.java
@@ -60,6 +60,8 @@ public class Bug572629 {
 		new Bug572629("p").equals(new Bug572629("r"));
 		new Bug572629("p").hoverOverLocal(new String[] {"name"});
 		new Bug572629("p").hoverOnThis();
+		Bug572629 local = new Bug572629("p");
+		System.out.println(local.names.length);
 	}
 
 	public static class Parent {
@@ -72,4 +74,5 @@ public class Bug572629 {
 		public String name = "name";
 	}
 	
+	public String[] names = new String[]{"foo"};
 }
\ No newline at end of file
diff --git a/org.eclipse.jdt.debug.tests/tests/org/eclipse/jdt/debug/tests/ui/DebugHoverTests.java b/org.eclipse.jdt.debug.tests/tests/org/eclipse/jdt/debug/tests/ui/DebugHoverTests.java
index 037fc013e..89d20bee8 100644
--- a/org.eclipse.jdt.debug.tests/tests/org/eclipse/jdt/debug/tests/ui/DebugHoverTests.java
+++ b/org.eclipse.jdt.debug.tests/tests/org/eclipse/jdt/debug/tests/ui/DebugHoverTests.java
@@ -801,6 +801,117 @@ public class DebugHoverTests extends AbstractDebugUiTests {
 		}
 	}
 
+	public void testBug572629_onThisExpression() throws Exception {
+		sync(() -> TestUtil.waitForJobs(getName(), 1000, 10000, ProcessConsole.class));
+
+		final String typeName = "Bug572629";
+		final String expectedMethod = "equals";
+		final int frameNumber = 2;
+		final int bpLine = 37;
+
+		IJavaBreakpoint bp = createLineBreakpoint(bpLine, "", typeName + ".java", typeName);
+		bp.setSuspendPolicy(IJavaBreakpoint.SUSPEND_THREAD);
+		IFile file = (IFile) bp.getMarker().getResource();
+		assertEquals(typeName + ".java", file.getName());
+
+		IJavaThread thread = null;
+		try {
+			thread = launchToBreakpoint(typeName);
+			CompilationUnitEditor part = openEditorAndValidateStack(expectedMethod, frameNumber, file, thread);
+
+			JavaDebugHover hover = new JavaDebugHover();
+			hover.setEditor(part);
+
+			String variableName = "payload";
+			int offset = part.getViewer().getDocument().get().indexOf("return this.payload") + "return this.".length();
+			IRegion region = new Region(offset, "payload".length());
+			String text = selectAndReveal(part, bpLine, region);
+			assertEquals(variableName, text);
+			IVariable info = (IVariable) sync(() -> hover.getHoverInfo2(part.getViewer(), region));
+
+			assertNotNull(info);
+			assertEquals("payload", info.getName());
+			assertEquals("p", info.getValue().getValueString());
+		} finally {
+			terminateAndRemove(thread);
+			removeAllBreakpoints();
+		}
+	}
+
+	public void testBug573223_onLocalVarChain_onArrayField() throws Exception {
+		sync(() -> TestUtil.waitForJobs(getName(), 1000, 10000, ProcessConsole.class));
+
+		final String typeName = "Bug572629";
+		final String expectedMethod = "main";
+		final int frameNumber = 1;
+		final int bpLine = 64;
+
+		IJavaBreakpoint bp = createLineBreakpoint(bpLine, "", typeName + ".java", typeName);
+		bp.setSuspendPolicy(IJavaBreakpoint.SUSPEND_THREAD);
+		IFile file = (IFile) bp.getMarker().getResource();
+		assertEquals(typeName + ".java", file.getName());
+
+		IJavaThread thread = null;
+		try {
+			thread = launchToBreakpoint(typeName);
+			CompilationUnitEditor part = openEditorAndValidateStack(expectedMethod, frameNumber, file, thread);
+
+			JavaDebugHover hover = new JavaDebugHover();
+			hover.setEditor(part);
+
+			String variableName = "names";
+			int offset = part.getViewer().getDocument().get().lastIndexOf("local.names") + "local.".length();
+			IRegion region = new Region(offset, "names".length());
+			String text = selectAndReveal(part, bpLine, region);
+			assertEquals(variableName, text);
+			IVariable info = (IVariable) sync(() -> hover.getHoverInfo2(part.getViewer(), region));
+
+			assertNotNull(info);
+			assertEquals("local.names", info.getName());
+			assertTrue("Not an array variable", info.getValue() instanceof IJavaArray);
+		} finally {
+			terminateAndRemove(thread);
+			removeAllBreakpoints();
+		}
+	}
+
+	public void testBug573223_onLocalVarChain_onArrayLength() throws Exception {
+		sync(() -> TestUtil.waitForJobs(getName(), 1000, 10000, ProcessConsole.class));
+
+		final String typeName = "Bug572629";
+		final String expectedMethod = "main";
+		final int frameNumber = 1;
+		final int bpLine = 64;
+
+		IJavaBreakpoint bp = createLineBreakpoint(bpLine, "", typeName + ".java", typeName);
+		bp.setSuspendPolicy(IJavaBreakpoint.SUSPEND_THREAD);
+		IFile file = (IFile) bp.getMarker().getResource();
+		assertEquals(typeName + ".java", file.getName());
+
+		IJavaThread thread = null;
+		try {
+			thread = launchToBreakpoint(typeName);
+			CompilationUnitEditor part = openEditorAndValidateStack(expectedMethod, frameNumber, file, thread);
+
+			JavaDebugHover hover = new JavaDebugHover();
+			hover.setEditor(part);
+
+			String variableName = "length";
+			int offset = part.getViewer().getDocument().get().lastIndexOf("local.names.length") + "local.names.".length();
+			IRegion region = new Region(offset, "length".length());
+			String text = selectAndReveal(part, bpLine, region);
+			assertEquals(variableName, text);
+			IVariable info = (IVariable) sync(() -> hover.getHoverInfo2(part.getViewer(), region));
+
+			assertNotNull(info);
+			assertEquals("local.names.length", info.getName());
+			assertEquals("1", info.getValue().getValueString());
+		} finally {
+			terminateAndRemove(thread);
+			removeAllBreakpoints();
+		}
+	}
+
 	private CompilationUnitEditor openEditorAndValidateStack(final String expectedMethod, final int expectedFramesNumber, IFile file, IJavaThread thread) throws Exception, DebugException {
 		// Let now all pending jobs proceed, ignore console jobs
 		sync(() -> TestUtil.waitForJobs(getName(), 1000, 10000, ProcessConsole.class));
diff --git a/org.eclipse.jdt.debug.ui/ui/org/eclipse/jdt/internal/debug/ui/JavaDebugHover.java b/org.eclipse.jdt.debug.ui/ui/org/eclipse/jdt/internal/debug/ui/JavaDebugHover.java
index 88742e15c..4076ce164 100644
--- a/org.eclipse.jdt.debug.ui/ui/org/eclipse/jdt/internal/debug/ui/JavaDebugHover.java
+++ b/org.eclipse.jdt.debug.ui/ui/org/eclipse/jdt/internal/debug/ui/JavaDebugHover.java
@@ -359,8 +359,9 @@ public class JavaDebugHover implements IJavaEditorTextHover, ITextHoverExtension
 								}
             		    	}
             		    } else {
-							if (!frame.isStatic() && !frame.isNative()) {
-            		    		// ensure that we only resolve a field access on 'this':
+							if ((!frame.isStatic() || isLocalOrMemberVariable(javaElement)) && !frame.isNative()) {
+								// we resolve chain elements which are either on "this" or local variables. In case of
+								// local variables we also consider static frames.
 								if (!(codeAssist instanceof ITypeRoot)) {
 									return null;
 								}