Add unit test for trailing lambda completions

Author: fwcd

server/src/test/kotlin/org/javacs/kt/CompletionsTest.kt

@@ -253,7 +253,7 @@ class EditCallTest : SingleFileTestFixture("completions", "EditCall.kt") {
         val labels = completions.items.map { it.label }
 
         assertThat(labels, hasItem(startsWith("println")))
-        assertThat(completions.items.filter { it.label.startsWith("println") }.firstOrNull(), hasProperty("insertText", equalTo("println")))
+        assertThat(completions.items.find { it.label.startsWith("println") }, hasProperty("insertText", equalTo("println")))
     }
 }
 
@@ -265,3 +265,21 @@ class EnumWithCompanionObjectTest : SingleFileTestFixture("completions", "Enum.k
         assertThat(labels, hasItem("ILLEGAL"))
     }
 }
+
+class TrailingLambdaTest : SingleFileTestFixture("completions", "TrailingLambda.kt") {
+    @Test fun `complete function with single lambda parameter`() {
+        val completions = languageServer.textDocumentService.completion(completionParams(file, 6, 9)).get().right!!
+        val labels = completions.items.map { it.label }
+
+        assertThat(labels, hasItem(startsWith("lambdaParameter")))
+        assertThat(completions.items.find { it.label.startsWith("lambdaParameter") }, hasProperty("insertText", equalTo("lambdaParameter { \${1:x} }")))
+    }
+
+    @Test fun `complete function with mixed parameters`() {
+        val completions = languageServer.textDocumentService.completion(completionParams(file, 7, 8)).get().right!!
+        val labels = completions.items.map { it.label }
+
+        assertThat(labels, hasItem(startsWith("mixedParameters")))
+        assertThat(completions.items.find { it.label.startsWith("mixedParameters") }, hasProperty("insertText", equalTo("mixedParameters(\${1:a}) { \${2:b} }")))
+    }
+}

server/src/test/resources/completions/TrailingLambda.kt

@@ -0,0 +1,8 @@
+fun lambdaParameter(x: () -> Unit) {}
+
+fun mixedParameters(a: Int, b: (Int) -> Unit) {}
+
+fun main(args: Array<String>) {
+    lamb
+    mix
+}