Add new line comment when pressing Enter from within line comment for languages that use double slash for line comment (#235407)

* add decrease and increase indent patterns for cpp

* adding new line with line comment on next line from within languages that use double slash for line comment

extensions/groovy/language-configuration.json

@@ -1,25 +1,88 @@
 {
 	"comments": {
 		"lineComment": "//",
-		"blockComment": [ "/*", "*/" ]
+		"blockComment": [
+			"/*",
+			"*/"
+		]
 	},
 	"brackets": [
-		["{", "}"],
-		["[", "]"],
-		["(", ")"]
+		[
+			"{",
+			"}"
+		],
+		[
+			"[",
+			"]"
+		],
+		[
+			"(",
+			")"
+		]
 	],
 	"autoClosingPairs": [
-		["{", "}"],
-		["[", "]"],
-		["(", ")"],
-		{ "open": "\"", "close": "\"", "notIn": ["string"] },
-		{ "open": "'", "close": "'", "notIn": ["string"] }
+		[
+			"{",
+			"}"
+		],
+		[
+			"[",
+			"]"
+		],
+		[
+			"(",
+			")"
+		],
+		{
+			"open": "\"",
+			"close": "\"",
+			"notIn": [
+				"string"
+			]
+		},
+		{
+			"open": "'",
+			"close": "'",
+			"notIn": [
+				"string"
+			]
+		}
 	],
 	"surroundingPairs": [
-		["{", "}"],
-		["[", "]"],
-		["(", ")"],
-		["\"", "\""],
-		["'", "'"]
+		[
+			"{",
+			"}"
+		],
+		[
+			"[",
+			"]"
+		],
+		[
+			"(",
+			")"
+		],
+		[
+			"\"",
+			"\""
+		],
+		[
+			"'",
+			"'"
+		]
+	],
+	"onEnterRules": [
+		// Add // when pressing enter from inside line comment
+		{
+			"beforeText": {
+				"pattern": "\/\/.*"
+			},
+			"afterText": {
+				"pattern": "^(?!\\s*$).+"
+			},
+			"action": {
+				"indent": "none",
+				"appendText": "// "
+			}
+		},
 	]
 }