Provide ConvertToValFix for READ_ONLY_VALUE_CANNOT_BE_VAR

tools/intellij-plugin/run/projects/test-project/build.gradle.kts

@@ -1,7 +1,7 @@
 plugins {
     kotlin("jvm") version "1.4.20"
     kotlin("plugin.serialization") version "1.4.20"
-    id("net.mamoe.mirai-console") version "1.1.0-dev-33"
+    id("net.mamoe.mirai-console") version "1.1.0-dev-36"
 }
 
 group = "org.example"

tools/intellij-plugin/run/projects/test-project/src/main/kotlin/org/example/myplugin/MySimpleCommand.kt

@@ -28,7 +28,7 @@ object DataTest : AutoSavePluginConfig("data") {
 }
 
 object DataTest1 : ReadOnlyPluginConfig("data") {
-    var pp by value<String>()
+    val pp by value<String>()
 }
 
 @Serializable

tools/intellij-plugin/src/QuickFixRegistrar.kt

@@ -12,6 +12,7 @@ package net.mamoe.mirai.console.intellij
 import com.intellij.codeInsight.intention.IntentionAction
 import net.mamoe.mirai.console.compiler.common.diagnostics.MiraiConsoleErrors
 import net.mamoe.mirai.console.intellij.diagnostics.fix.AddSerializerFix
+import net.mamoe.mirai.console.intellij.diagnostics.fix.ConvertToValFix
 import net.mamoe.mirai.console.intellij.diagnostics.fix.ProvideDefaultValueFix
 import org.jetbrains.kotlin.diagnostics.DiagnosticFactory
 import org.jetbrains.kotlin.idea.quickfix.KotlinIntentionActionsFactory
@@ -31,5 +32,6 @@ class QuickFixRegistrar : QuickFixContributor {
 
         MiraiConsoleErrors.UNSERIALIZABLE_TYPE.registerFactory(AddSerializerFix)
         MiraiConsoleErrors.NOT_CONSTRUCTABLE_TYPE.registerFactory(ProvideDefaultValueFix)
+        MiraiConsoleErrors.READ_ONLY_VALUE_CANNOT_BE_VAR.registerFactory(ConvertToValFix)
     }
 }

tools/intellij-plugin/src/diagnostics/fix/ConvertToValFix.kt

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2019-2020 Mamoe Technologies and contributors.
+ *
+ * 此源代码的使用受 GNU AFFERO GENERAL PUBLIC LICENSE version 3 许可证的约束, 可以在以下链接找到该许可证.
+ * Use of this source code is governed by the GNU AFFERO GENERAL PUBLIC LICENSE version 3 license that can be found through the following link.
+ *
+ * https://github.com/mamoe/mirai/blob/master/LICENSE
+ */
+
+package net.mamoe.mirai.console.intellij.diagnostics.fix
+
+import com.intellij.codeInsight.intention.IntentionAction
+import com.intellij.openapi.editor.Editor
+import com.intellij.openapi.project.Project
+import com.intellij.psi.PsiElement
+import com.intellij.psi.PsiFile
+import net.mamoe.mirai.console.compiler.common.castOrNull
+import net.mamoe.mirai.console.compiler.common.diagnostics.MiraiConsoleErrors
+import org.jetbrains.kotlin.diagnostics.Diagnostic
+import org.jetbrains.kotlin.diagnostics.SimpleDiagnostic
+import org.jetbrains.kotlin.idea.inspections.KotlinUniversalQuickFix
+import org.jetbrains.kotlin.idea.quickfix.KotlinCrossLanguageQuickFixAction
+import org.jetbrains.kotlin.idea.quickfix.KotlinSingleIntentionActionFactory
+import org.jetbrains.kotlin.idea.util.application.executeWriteCommand
+import org.jetbrains.kotlin.psi.KtPsiFactory
+
+/**
+ * @see MiraiConsoleErrors.READ_ONLY_VALUE_CANNOT_BE_VAR
+ */
+class ConvertToValFix(
+    element: PsiElement,
+) : KotlinCrossLanguageQuickFixAction<PsiElement>(element), KotlinUniversalQuickFix {
+
+    override fun getFamilyName(): String = "Mirai Console"
+    override fun getText(): String = "转换为 val"
+
+    override fun invokeImpl(project: Project, editor: Editor?, file: PsiFile) {
+        val element = element ?: return
+        project.executeWriteCommand(name) {
+            element.replace(KtPsiFactory(project).createValKeyword())
+        }
+    }
+
+    companion object : KotlinSingleIntentionActionFactory() {
+        override fun createAction(diagnostic: Diagnostic): IntentionAction? {
+            val diagnostic1 = diagnostic.castOrNull<SimpleDiagnostic<PsiElement>>() ?: return null
+            return ConvertToValFix(diagnostic1.psiElement)
+        }
+
+        override fun isApplicableForCodeFragment(): Boolean = false
+    }
+}