From 7406ee9c145cd7d6117391818d5a1eca2d66ca8f Mon Sep 17 00:00:00 2001
From: Oleksandr T <oleksandr.tarasiuk@outlook.com>
Date: Mon, 17 Oct 2022 23:14:23 +0300
Subject: [PATCH] fix(51170): Completing an unimplemented property overwrites
 rest of line (#51175)

* fix(51170): skip insertText for class members with existing initializer

* skip insertText for class members with existing tokens
---
 src/services/completions.ts                   |  5 +++--
 ...ts => completionsOverridingProperties1.ts} |  0
 .../completionsOverridingProperties2.ts       | 21 +++++++++++++++++++
 .../completionsOverridingProperties3.ts       | 21 +++++++++++++++++++
 4 files changed, 45 insertions(+), 2 deletions(-)
 rename tests/cases/fourslash/{completionsOverridingProperties.ts => completionsOverridingProperties1.ts} (100%)
 create mode 100644 tests/cases/fourslash/completionsOverridingProperties2.ts
 create mode 100644 tests/cases/fourslash/completionsOverridingProperties3.ts

diff --git a/src/services/completions.ts b/src/services/completions.ts
index bff90e2d3e7c5..9bdc38195da54 100644
--- a/src/services/completions.ts
+++ b/src/services/completions.ts
@@ -764,7 +764,7 @@ namespace ts.Completions {
         if (preferences.includeCompletionsWithClassMemberSnippets &&
             preferences.includeCompletionsWithInsertText &&
             completionKind === CompletionKind.MemberLike &&
-            isClassLikeMemberCompletion(symbol, location)) {
+            isClassLikeMemberCompletion(symbol, location, sourceFile)) {
             let importAdder;
             ({ insertText, isSnippet, importAdder, replacementSpan } = getEntryForMemberCompletion(host, program, options, preferences, name, symbol, location, contextToken, formatContext));
             sortText = SortText.ClassMemberSnippets; // sortText has to be lower priority than the sortText for keywords. See #47852.
@@ -846,7 +846,7 @@ namespace ts.Completions {
         };
     }
 
-    function isClassLikeMemberCompletion(symbol: Symbol, location: Node): boolean {
+    function isClassLikeMemberCompletion(symbol: Symbol, location: Node, sourceFile: SourceFile): boolean {
         // TODO: support JS files.
         if (isInJSFile(location)) {
             return false;
@@ -884,6 +884,7 @@ namespace ts.Completions {
                     location.parent.parent &&
                     isClassElement(location.parent) &&
                     location === location.parent.name &&
+                    location.parent.getLastToken(sourceFile) === location.parent.name &&
                     isClassLike(location.parent.parent)
                 ) ||
                 (
diff --git a/tests/cases/fourslash/completionsOverridingProperties.ts b/tests/cases/fourslash/completionsOverridingProperties1.ts
similarity index 100%
rename from tests/cases/fourslash/completionsOverridingProperties.ts
rename to tests/cases/fourslash/completionsOverridingProperties1.ts
diff --git a/tests/cases/fourslash/completionsOverridingProperties2.ts b/tests/cases/fourslash/completionsOverridingProperties2.ts
new file mode 100644
index 0000000000000..8938b8bb7fe68
--- /dev/null
+++ b/tests/cases/fourslash/completionsOverridingProperties2.ts
@@ -0,0 +1,21 @@
+/// <reference path="fourslash.ts" />
+
+////interface I {
+////    prop: string;
+////}
+////class C implements I {
+////    public pr/**/: string = 'foo';
+////}
+
+verify.completions({
+    marker: "",
+    includes: [
+        { name: "prop", isSnippet: undefined, insertText: undefined }
+    ],
+    isNewIdentifierLocation: true,
+    preferences: {
+        includeCompletionsWithInsertText: true,
+        includeCompletionsWithSnippetText: true,
+        includeCompletionsWithClassMemberSnippets: true,
+    }
+});
diff --git a/tests/cases/fourslash/completionsOverridingProperties3.ts b/tests/cases/fourslash/completionsOverridingProperties3.ts
new file mode 100644
index 0000000000000..c13ddadd90b89
--- /dev/null
+++ b/tests/cases/fourslash/completionsOverridingProperties3.ts
@@ -0,0 +1,21 @@
+/// <reference path="fourslash.ts" />
+
+////interface I {
+////    prop: string;
+////}
+////class C implements I {
+////    public pr/**/: string | number;
+////}
+
+verify.completions({
+    marker: "",
+    includes: [
+        { name: "prop", isSnippet: undefined, insertText: undefined }
+    ],
+    isNewIdentifierLocation: true,
+    preferences: {
+        includeCompletionsWithInsertText: true,
+        includeCompletionsWithSnippetText: true,
+        includeCompletionsWithClassMemberSnippets: true,
+    }
+});