From 45e3f6660cf4503a8f63ce0a22e574f6d0997914 Mon Sep 17 00:00:00 2001
From: Hector Diaz <hdiaz@fb.com>
Date: Thu, 30 Jan 2020 15:07:49 -0800
Subject: [PATCH] Auto-completion bug fix for dot operator

Summary:
There was a bug on LLDB VSCode where there was the following behavior:

//Code

```
struct foo {
    int bar:
};
...
foo my_foo = {10};
```

Trying to auto-complete my_foo.b with my_foo.bar resulted instead with my_foo.my_foo.bar

This diff fixes this bug and adds some tests to check correct behavior.

It also fixes the same bug using the arrow operator (->) when user manually requests completions.
TODO: Fix bug where no recommended completions are automatically shown with arrow operator

{F11249959}

{F11249958}

Reviewers: wallace

Reviewed By: wallace

Subscribers: teemperor, labath, lldb-commits

Tags: #lldb

Differential Revision: https://reviews.llvm.org/D73506
---
 .../completions/TestVSCode_completions.py          | 73 ++++++++++++++++++++++
 .../test/tools/lldb-vscode/completions/main.cpp    | 14 +++++
 lldb/tools/lldb-vscode/lldb-vscode.cpp             | 12 +++-
 3 files changed, 97 insertions(+), 2 deletions(-)

diff --git a/lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/completions/TestVSCode_completions.py b/lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/completions/TestVSCode_completions.py
index d1d9234..155d476 100644
--- a/lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/completions/TestVSCode_completions.py
+++ b/lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/completions/TestVSCode_completions.py
@@ -113,3 +113,76 @@ class TestVSCode_variables(lldbvscode_testcase.VSCodeTestCaseBase):
                 }
             ],
         )
+
+        self.verify_completions(
+            self.vscode.get_completions("foo1.v"),
+            [
+                {
+                    "text": "var1",
+                    "label": "foo1.var1 -- int"
+                }
+            ]
+        )
+
+        self.verify_completions(
+            self.vscode.get_completions("foo1.my_bar_object.v"),
+            [
+                {
+                    "text": "var1",
+                    "label": "foo1.my_bar_object.var1 -- int"
+                }
+            ]
+        )
+
+        self.verify_completions(
+            self.vscode.get_completions("foo1.var1 + foo1.v"),
+            [
+                {
+                    "text": "var1",
+                    "label": "foo1.var1 -- int"
+                }
+            ]
+        )
+
+        self.verify_completions(
+            self.vscode.get_completions("foo1.var1 + v"),
+            [
+                {
+                    "text": "var1",
+                    "label": "var1 -- int &"
+                }
+            ]
+        )
+
+        #should correctly handle spaces between objects and member operators
+        self.verify_completions(
+            self.vscode.get_completions("foo1 .v"),
+            [
+                {
+                    "text": "var1",
+                    "label": ".var1 -- int"
+                }
+            ],
+            [
+                {
+                    "text": "var2",
+                    "label": ".var2 -- int"
+                }
+            ]
+        )
+
+        self.verify_completions(
+            self.vscode.get_completions("foo1 . v"),
+            [
+                {
+                    "text": "var1",
+                    "label": "var1 -- int"
+                }
+            ], 
+            [
+                {
+                    "text": "var2",
+                    "label": "var2 -- int"
+                }
+            ]
+        )
diff --git a/lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/completions/main.cpp b/lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/completions/main.cpp
index 14a8815..f77dba5 100644
--- a/lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/completions/main.cpp
+++ b/lldb/packages/Python/lldbsuite/test/tools/lldb-vscode/completions/main.cpp
@@ -1,6 +1,17 @@
 #include <string>
 #include <vector>
 
+struct bar {
+  int var1;
+};
+
+struct foo {
+  int var1;
+  bar* my_bar_pointer;
+  bar my_bar_object;
+  foo* next_foo;
+};
+
 int fun(std::vector<std::string> var) {
   return var.size(); // breakpoint 1
 }
@@ -12,5 +23,8 @@ int main(int argc, char const *argv[]) {
   std::string str2 = "b";
   std::vector<std::string> vec;
   fun(vec);
+  bar bar1 = {2};
+  bar* bar2 = &bar1; 
+  foo foo1 = {3,&bar1, bar1, NULL};
   return 0; // breakpoint 2
 }
diff --git a/lldb/tools/lldb-vscode/lldb-vscode.cpp b/lldb/tools/lldb-vscode/lldb-vscode.cpp
index 8fad2a5..83ea236 100644
--- a/lldb/tools/lldb-vscode/lldb-vscode.cpp
+++ b/lldb/tools/lldb-vscode/lldb-vscode.cpp
@@ -951,9 +951,17 @@ void request_completions(const llvm::json::Object &request) {
   for (size_t i = 0; i < count; i++) {
     std::string match = matches.GetStringAtIndex(i);
     std::string description = descriptions.GetStringAtIndex(i);
-
+    
     llvm::json::Object item;
-    EmplaceSafeString(item, "text", match);
+
+    llvm::StringRef match_ref = match;
+    for(llvm::StringRef commit_point: {".", "->"}) {
+      if (match_ref.contains(commit_point)){
+        match_ref = match_ref.rsplit(commit_point).second;
+      }
+    }
+    EmplaceSafeString(item, "text", match_ref);
+
     if (description.empty())
       EmplaceSafeString(item, "label", match);
     else
-- 
2.7.4