Merge pull request #220 from Teemperor/BackportFrameVarFix

[lldb] Reland 370734: Test 'frame select -r' and fix that INT32_MIN b…

Author: JDevlieghere

lldb/packages/Python/lldbsuite/test/commands/frame/select/TestFrameSelect.py

@@ -36,3 +36,42 @@ def test_relative(self):
 
         self.expect("frame select -r 100")
         self.expect("frame select -r 1", error=True, substrs=["Already at the top of the stack."])
+
+    @no_debug_info_test
+    @skipIfWindows
+    def test_mixing_relative_and_abs(self):
+        self.build()
+
+        lldbutil.run_to_source_breakpoint(self,
+            "// Set break point at this line.", lldb.SBFileSpec("main.cpp"))
+
+        # The function associated with each frame index can change depending
+        # on the function calling main (e.g. `start`), so this only tests that
+        # the frame index number is correct. We test the actual functions
+        # in the relative test.
+
+        # Jump to the top of the stack.
+        self.expect("frame select 0", substrs=["frame #0"])
+
+        # Run some relative commands.
+        self.expect("up", substrs=["frame #1"])
+        self.expect("frame select -r 1", substrs=["frame #2"])
+        self.expect("frame select -r -1", substrs=["frame #1"])
+
+        # Test that absolute indices still work.
+        self.expect("frame select 2", substrs=["frame #2"])
+        self.expect("frame select 1", substrs=["frame #1"])
+        self.expect("frame select 3", substrs=["frame #3"])
+        self.expect("frame select 0", substrs=["frame #0"])
+        self.expect("frame select 1", substrs=["frame #1"])
+
+        # Run some other relative frame select commands.
+        self.expect("down", substrs=["frame #0"])
+        self.expect("frame select -r 1", substrs=["frame #1"])
+        self.expect("frame select -r -1", substrs=["frame #0"])
+
+        # Test that absolute indices still work.
+        self.expect("frame select 2", substrs=["frame #2"])
+        self.expect("frame select 1", substrs=["frame #1"])
+        self.expect("frame select 3", substrs=["frame #3"])
+        self.expect("frame select 0", substrs=["frame #0"])

lldb/source/Commands/CommandObjectFrame.cpp

@@ -263,8 +263,10 @@ class CommandObjectFrameSelect : public CommandObjectParsed {
       return error;
     }
 
-    void OptionParsingStarting(ExecutionContext *execution_context) override {}
-    
+    void OptionParsingStarting(ExecutionContext *execution_context) override {
+      relative_frame_offset.reset();
+    }
+
     llvm::ArrayRef<OptionDefinition> GetDefinitions() override {
       return llvm::makeArrayRef(g_frame_select_options);
     }