Do prefix matching before creating shadow lookup elements

Author: Earthcomputer

src/main/kotlin/platform/mixin/completion/MixinCompletionContributor.kt

@@ -32,7 +32,7 @@ import com.intellij.codeInsight.completion.CompletionType
 import com.intellij.codeInsight.completion.JavaCompletionContributor
 import com.intellij.codeInsight.completion.JavaCompletionSorting
 import com.intellij.codeInsight.completion.LegacyCompletionContributor
-import com.intellij.codeInsight.completion.PrioritizedLookupElement
+import com.intellij.openapi.util.text.StringUtil
 import com.intellij.psi.PsiClassType
 import com.intellij.psi.PsiExpression
 import com.intellij.psi.PsiJavaReference
@@ -107,8 +107,11 @@ class MixinCompletionContributor : CompletionContributor() {
 
             // Process methods and fields from target class
             val elements = findShadowTargets(psiClass, start, superMixin != null)
+                .filter {
+                    val name = it.name
+                    StringUtil.isJavaIdentifier(name) && prefixMatcher.prefixMatches(name)
+                }
                 .map { it.createLookupElement(psiClass.project) }
-                .filter { prefixMatcher.prefixMatches(it) }
                 .filter(filter, position)
                 .toList()
 

src/main/kotlin/platform/mixin/util/TargetClass.kt

@@ -120,6 +120,7 @@ private fun findShadowTargetsDeep(psiClass: PsiClass, start: PsiClass): Sequence
 
 sealed class MixinTargetMember(val mixin: PsiClass?) {
     abstract val access: Int
+    abstract val name: String
 
     abstract fun findSourceElement(
         project: Project,
@@ -138,6 +139,7 @@ class FieldTargetMember(val classAndField: ClassAndFieldNode, mixin: PsiClass? =
     constructor(clazz: ClassNode, field: FieldNode) : this(ClassAndFieldNode(clazz, field))
 
     override val access = classAndField.field.access
+    override val name: String = classAndField.field.name
 
     override fun findSourceElement(project: Project, scope: GlobalSearchScope, canDecompile: Boolean) =
         classAndField.field.findSourceField(classAndField.clazz, project, scope, canDecompile)
@@ -153,6 +155,7 @@ class MethodTargetMember(val classAndMethod: ClassAndMethodNode, mixin: PsiClass
     constructor(clazz: ClassNode, method: MethodNode) : this(ClassAndMethodNode(clazz, method))
 
     override val access = classAndMethod.method.access
+    override val name: String = classAndMethod.method.name
 
     override fun findSourceElement(project: Project, scope: GlobalSearchScope, canDecompile: Boolean) =
         classAndMethod.method.findSourceElement(classAndMethod.clazz, project, scope, canDecompile)