From b8eee9d001a8d28a7fb17829df6353859b7be906 Mon Sep 17 00:00:00 2001
From: Mark Punzalan <markpun@google.com>
Date: Sat, 4 Sep 2021 08:26:06 +0000
Subject: [PATCH] KotlinHighLevelFunctionParameterInfoHandler: Properly handle
 vararg parameter arguments.

The computation for which parameter to highlight did not account for
multiple arguments for vararg parameters.

GitOrigin-RevId: dce019225af47749425c80c628332a895a549a57
---
 ...inHighLevelFunctionParameterInfoHandler.kt | 33 ++++++++++++++++---
 .../FirParameterInfoTestGenerated.java        | 30 +++++++++++++++++
 .../ParameterInfoTestGenerated.java           | 30 +++++++++++++++++
 .../parameterInfo/functionCall/Vararg.kt      |  8 +++++
 .../VarargFirstArgTrailingComma.kt            |  8 +++++
 .../VarargMultipleArgsTrailingComma.kt        |  8 +++++
 .../functionCall/VarargNamedArg.kt            |  9 +++++
 .../functionCall/VarargSpreadArg.kt           |  9 +++++
 .../functionCall/VarargUpdateOnTyping.kt      | 11 +++++++
 9 files changed, 141 insertions(+), 5 deletions(-)
 create mode 100644 plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/Vararg.kt
 create mode 100644 plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargFirstArgTrailingComma.kt
 create mode 100644 plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargMultipleArgsTrailingComma.kt
 create mode 100644 plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargNamedArg.kt
 create mode 100644 plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargSpreadArg.kt
 create mode 100644 plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargUpdateOnTyping.kt

diff --git a/plugins/kotlin/fir/src/org/jetbrains/kotlin/idea/parameterInfo/KotlinHighLevelFunctionParameterInfoHandler.kt b/plugins/kotlin/fir/src/org/jetbrains/kotlin/idea/parameterInfo/KotlinHighLevelFunctionParameterInfoHandler.kt
index 99cee337030a..bb85d33f99a9 100644
--- a/plugins/kotlin/fir/src/org/jetbrains/kotlin/idea/parameterInfo/KotlinHighLevelFunctionParameterInfoHandler.kt
+++ b/plugins/kotlin/fir/src/org/jetbrains/kotlin/idea/parameterInfo/KotlinHighLevelFunctionParameterInfoHandler.kt
@@ -191,6 +191,23 @@ abstract class KotlinHighLevelParameterInfoWithCallHandlerBase<TArgumentList : K
                     }
                 }
 
+                // Determine the parameter to be highlighted.
+                val afterTrailingComma = arguments.isNotEmpty() && currentArgumentIndex == arguments.size
+                val highlightParameterIndex = when {
+                    currentArgumentIndex < arguments.size -> argumentToParameterIndex[arguments[currentArgumentIndex]]
+                    afterTrailingComma -> {
+                        // If last argument is for a vararg parameter, then the argument about to be entered at the cursor should also be
+                        // for that same vararg parameter.
+                        val parameterForLastArgument = argumentMapping[arguments.last()]
+                        if (parameterForLastArgument?.isVararg == true) {
+                            parameterToIndex[parameterForLastArgument]
+                        } else {
+                            null
+                        }
+                    }
+                    else -> null
+                }
+
                 var hasTypeMismatchBeforeCurrent = false
                 for ((index, argument) in arguments.withIndex()) {
                     if (index >= currentArgumentIndex) break
@@ -216,7 +233,8 @@ abstract class KotlinHighLevelParameterInfoWithCallHandlerBase<TArgumentList : K
                     valueParameters.size,
                     parameterIndexToText,
                     isCallResolvedToCandidate,
-                    hasTypeMismatchBeforeCurrent
+                    hasTypeMismatchBeforeCurrent,
+                    highlightParameterIndex,
                 )
             }
         }
@@ -315,7 +333,7 @@ abstract class KotlinHighLevelParameterInfoWithCallHandlerBase<TArgumentList : K
 
         val callInfo = itemToShow.callInfo ?: return false
         val (callElement, valueArguments, arguments, argumentToParameterIndex, valueParameterCount, parameterIndexToText,
-            isCallResolvedToCandidate, hasTypeMismatchBeforeCurrent) = callInfo
+            isCallResolvedToCandidate, hasTypeMismatchBeforeCurrent, highlightParameterIndex) = callInfo
 
         val supportsMixedNamedArgumentsInTheirOwnPosition =
             callElement.languageVersionSettings.supportsFeature(LanguageFeature.MixedNamedArgumentsInTheirOwnPosition)
@@ -333,6 +351,7 @@ abstract class KotlinHighLevelParameterInfoWithCallHandlerBase<TArgumentList : K
         var highlightStartOffset = -1
         var highlightEndOffset = -1
         var isDisabledBeforeHighlight = false
+        var hasUnmappedArgument = false
         var hasUnmappedArgumentBeforeCurrent = false
         val usedParameterIndices = HashSet<Int>()
         val text = buildString {
@@ -383,6 +402,7 @@ abstract class KotlinHighLevelParameterInfoWithCallHandlerBase<TArgumentList : K
                 for (valueArgument in valueArguments) {
                     val parameterIndex = argumentToParameterIndex[valueArgument.getArgumentExpression()]
                     if (parameterIndex == null) {
+                        hasUnmappedArgument = true
                         if (argumentIndex < currentArgumentIndex) {
                             hasUnmappedArgumentBeforeCurrent = true
                         }
@@ -399,7 +419,7 @@ abstract class KotlinHighLevelParameterInfoWithCallHandlerBase<TArgumentList : K
                         namedMode = true
                     }
 
-                    val shouldHighlight = argumentIndex == currentArgumentIndex
+                    val shouldHighlight = parameterIndex == highlightParameterIndex
                     appendParameter(parameterIndex, shouldHighlight, valueArgument.isNamed())
                 }
             } else {
@@ -407,6 +427,7 @@ abstract class KotlinHighLevelParameterInfoWithCallHandlerBase<TArgumentList : K
                 for (argument in arguments) {
                     val parameterIndex = argumentToParameterIndex[argument]
                     if (parameterIndex == null) {
+                        hasUnmappedArgument = true
                         if (argumentIndex <= currentArgumentIndex) {
                             hasUnmappedArgumentBeforeCurrent = true
                         }
@@ -415,7 +436,7 @@ abstract class KotlinHighLevelParameterInfoWithCallHandlerBase<TArgumentList : K
                     }
                     if (!usedParameterIndices.add(parameterIndex)) continue
 
-                    val shouldHighlight = argumentIndex == currentArgumentIndex
+                    val shouldHighlight = parameterIndex == highlightParameterIndex
                     appendParameter(parameterIndex, shouldHighlight)
                 }
             }
@@ -447,7 +468,8 @@ abstract class KotlinHighLevelParameterInfoWithCallHandlerBase<TArgumentList : K
         val allParametersUsed = usedParameterIndices.size == valueParameterCount
         val supportsTrailingCommas = callElement.languageVersionSettings.supportsFeature(LanguageFeature.TrailingCommas)
         val afterTrailingComma = arguments.isNotEmpty() && currentArgumentIndex == arguments.size
-        val tooManyArgs = allParametersUsed && ((!supportsTrailingCommas && afterTrailingComma) || arguments.size > valueParameterCount)
+        val isInPositionToEnterArgument = !supportsTrailingCommas && afterTrailingComma
+        val tooManyArgs = allParametersUsed && (isInPositionToEnterArgument || hasUnmappedArgument)
 
         val isDisabled = tooManyArgs || hasTypeMismatchBeforeCurrent || hasUnmappedArgumentBeforeCurrent
 
@@ -473,6 +495,7 @@ abstract class KotlinHighLevelParameterInfoWithCallHandlerBase<TArgumentList : K
         val parameterIndexToText: Map<Int, String>,
         val isCallResolvedToCandidate: Boolean,
         val hasTypeMismatchBeforeCurrent: Boolean,
+        val highlightParameterIndex: Int?,
     )
 
     data class CandidateInfo(
diff --git a/plugins/kotlin/fir/test/org/jetbrains/kotlin/idea/fir/parameterInfo/FirParameterInfoTestGenerated.java b/plugins/kotlin/fir/test/org/jetbrains/kotlin/idea/fir/parameterInfo/FirParameterInfoTestGenerated.java
index 17bea12e2cea..d0ce3ca8d992 100644
--- a/plugins/kotlin/fir/test/org/jetbrains/kotlin/idea/fir/parameterInfo/FirParameterInfoTestGenerated.java
+++ b/plugins/kotlin/fir/test/org/jetbrains/kotlin/idea/fir/parameterInfo/FirParameterInfoTestGenerated.java
@@ -436,6 +436,36 @@ public abstract class FirParameterInfoTestGenerated extends AbstractFirParameter
         public void testUpdateOnTyping() throws Exception {
             runTest("../idea/tests/testData/parameterInfo/functionCall/UpdateOnTyping.kt");
         }
+
+        @TestMetadata("Vararg.kt")
+        public void testVararg() throws Exception {
+            runTest("../idea/tests/testData/parameterInfo/functionCall/Vararg.kt");
+        }
+
+        @TestMetadata("VarargFirstArgTrailingComma.kt")
+        public void testVarargFirstArgTrailingComma() throws Exception {
+            runTest("../idea/tests/testData/parameterInfo/functionCall/VarargFirstArgTrailingComma.kt");
+        }
+
+        @TestMetadata("VarargMultipleArgsTrailingComma.kt")
+        public void testVarargMultipleArgsTrailingComma() throws Exception {
+            runTest("../idea/tests/testData/parameterInfo/functionCall/VarargMultipleArgsTrailingComma.kt");
+        }
+
+        @TestMetadata("VarargNamedArg.kt")
+        public void testVarargNamedArg() throws Exception {
+            runTest("../idea/tests/testData/parameterInfo/functionCall/VarargNamedArg.kt");
+        }
+
+        @TestMetadata("VarargSpreadArg.kt")
+        public void testVarargSpreadArg() throws Exception {
+            runTest("../idea/tests/testData/parameterInfo/functionCall/VarargSpreadArg.kt");
+        }
+
+        @TestMetadata("VarargUpdateOnTyping.kt")
+        public void testVarargUpdateOnTyping() throws Exception {
+            runTest("../idea/tests/testData/parameterInfo/functionCall/VarargUpdateOnTyping.kt");
+        }
     }
 
     @RunWith(JUnit3RunnerWithInners.class)
diff --git a/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/parameterInfo/ParameterInfoTestGenerated.java b/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/parameterInfo/ParameterInfoTestGenerated.java
index e59b6ea335c3..099edea3299a 100644
--- a/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/parameterInfo/ParameterInfoTestGenerated.java
+++ b/plugins/kotlin/idea/tests/test/org/jetbrains/kotlin/idea/parameterInfo/ParameterInfoTestGenerated.java
@@ -436,6 +436,36 @@ public abstract class ParameterInfoTestGenerated extends AbstractParameterInfoTe
         public void testUpdateOnTyping() throws Exception {
             runTest("testData/parameterInfo/functionCall/UpdateOnTyping.kt");
         }
+
+        @TestMetadata("Vararg.kt")
+        public void testVararg() throws Exception {
+            runTest("testData/parameterInfo/functionCall/Vararg.kt");
+        }
+
+        @TestMetadata("VarargFirstArgTrailingComma.kt")
+        public void testVarargFirstArgTrailingComma() throws Exception {
+            runTest("testData/parameterInfo/functionCall/VarargFirstArgTrailingComma.kt");
+        }
+
+        @TestMetadata("VarargMultipleArgsTrailingComma.kt")
+        public void testVarargMultipleArgsTrailingComma() throws Exception {
+            runTest("testData/parameterInfo/functionCall/VarargMultipleArgsTrailingComma.kt");
+        }
+
+        @TestMetadata("VarargNamedArg.kt")
+        public void testVarargNamedArg() throws Exception {
+            runTest("testData/parameterInfo/functionCall/VarargNamedArg.kt");
+        }
+
+        @TestMetadata("VarargSpreadArg.kt")
+        public void testVarargSpreadArg() throws Exception {
+            runTest("testData/parameterInfo/functionCall/VarargSpreadArg.kt");
+        }
+
+        @TestMetadata("VarargUpdateOnTyping.kt")
+        public void testVarargUpdateOnTyping() throws Exception {
+            runTest("testData/parameterInfo/functionCall/VarargUpdateOnTyping.kt");
+        }
     }
 
     @RunWith(JUnit3RunnerWithInners.class)
diff --git a/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/Vararg.kt b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/Vararg.kt
new file mode 100644
index 000000000000..4208d0faf51a
--- /dev/null
+++ b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/Vararg.kt
@@ -0,0 +1,8 @@
+fun m(x: Boolean, vararg y: Int) = 2
+
+fun d() {
+    m(true, 1, <caret>2)
+}
+/*
+Text: (x: Boolean, <highlight>vararg y: Int</highlight>), Disabled: false, Strikeout: false, Green: true
+*/
\ No newline at end of file
diff --git a/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargFirstArgTrailingComma.kt b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargFirstArgTrailingComma.kt
new file mode 100644
index 000000000000..10c1ab7c8f84
--- /dev/null
+++ b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargFirstArgTrailingComma.kt
@@ -0,0 +1,8 @@
+fun m(x: Boolean, vararg y: Int) = 2
+
+fun d() {
+    m(true,<caret>)
+}
+/*
+Text: (x: Boolean, <highlight>vararg y: Int</highlight>), Disabled: false, Strikeout: false, Green: true
+*/
\ No newline at end of file
diff --git a/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargMultipleArgsTrailingComma.kt b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargMultipleArgsTrailingComma.kt
new file mode 100644
index 000000000000..aae5e737c8a6
--- /dev/null
+++ b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargMultipleArgsTrailingComma.kt
@@ -0,0 +1,8 @@
+fun m(x: Boolean, vararg y: Int) = 2
+
+fun d() {
+    m(true, 1, 2,<caret>)
+}
+/*
+Text: (x: Boolean, <highlight>vararg y: Int</highlight>), Disabled: false, Strikeout: false, Green: true
+*/
\ No newline at end of file
diff --git a/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargNamedArg.kt b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargNamedArg.kt
new file mode 100644
index 000000000000..7ec9dbbf0ac9
--- /dev/null
+++ b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargNamedArg.kt
@@ -0,0 +1,9 @@
+fun m(x: Boolean, vararg y: Int) = 2
+
+fun d() {
+    val a = intArrayOf(1, 2, 3)
+    m(y = <caret>a, x = true)
+}
+/*
+Text: (<highlight>[vararg y: Int]</highlight>, [x: Boolean]), Disabled: false, Strikeout: false, Green: true
+*/
\ No newline at end of file
diff --git a/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargSpreadArg.kt b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargSpreadArg.kt
new file mode 100644
index 000000000000..817b19a3ce48
--- /dev/null
+++ b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargSpreadArg.kt
@@ -0,0 +1,9 @@
+fun m(x: Boolean, vararg y: Int) = 2
+
+fun d() {
+    val a = intArrayOf(1, 2, 3)
+    m(true, 1, *a<caret>, 4)
+}
+/*
+Text: (x: Boolean, <highlight>vararg y: Int</highlight>), Disabled: false, Strikeout: false, Green: true
+*/
\ No newline at end of file
diff --git a/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargUpdateOnTyping.kt b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargUpdateOnTyping.kt
new file mode 100644
index 000000000000..8e2835a893a8
--- /dev/null
+++ b/plugins/kotlin/idea/tests/testData/parameterInfo/functionCall/VarargUpdateOnTyping.kt
@@ -0,0 +1,11 @@
+fun m(x: Boolean, vararg y: Int) = 2
+
+fun d() {
+    m(true, <caret>)
+}
+
+// TYPE: "true, "
+
+/*
+Text: (x: Boolean, <highlight>vararg y: Int</highlight>), Disabled: true, Strikeout: false, Green: true
+*/
\ No newline at end of file