completion and reference resolving

Author: reeFridge

build.gradle

@@ -61,7 +61,9 @@ intellij {
 patchPluginXml {
     changeNotes """
       <ul>
-        <li>Support for 2020.1</li>
+        <li>Line comment action</li>
+        <li>Scope based reference resolving</li>
+        <li>Basic keywords completion</li>
       </ul>
       """
 }

src/main/kotlin/com/interfaced/brs/lang/completion/BrsCompletionContributor.kt

@@ -0,0 +1,74 @@
+package com.interfaced.brs.lang.completion
+
+import com.intellij.codeInsight.completion.*
+import com.intellij.codeInsight.lookup.LookupElementBuilder
+import com.intellij.patterns.PlatformPatterns.psiElement
+import com.intellij.patterns.StandardPatterns
+import com.intellij.util.ProcessingContext
+import com.interfaced.brs.lang.psi.BrsTypes.T_AS
+import com.interfaced.brs.lang.psi.BrsTypes.T_LINE_TERMINATOR
+
+class BrsCompletionContributor : CompletionContributor() {
+    private object KeywordCompletionProvider : CompletionProvider<CompletionParameters>() {
+        private val keywords = listOf(
+                "And",
+                "Dim",
+                "Each",
+                "Else",
+                "ElseIf",
+                "End",
+                "EndFunction",
+                "EndIf",
+                "EndSub",
+                "EndWhile",
+                "Exit",
+                "ExitWhile",
+                "False",
+                "For",
+                "Function",
+                "Goto",
+                "If",
+                "Next",
+                "Not",
+                "Or",
+                "Print",
+                "Rem",
+                "Return",
+                "Step",
+                "Stop",
+                "Sub",
+                "Then",
+                "To",
+                "True",
+                "While"
+        )
+        override fun addCompletions(parameters: CompletionParameters, context: ProcessingContext, resultSet: CompletionResultSet) {
+            resultSet.addAllElements(listOf(keywords, keywords.map { it.toLowerCase() })
+                    .flatMap { it.map { str -> LookupElementBuilder.create(str) } })
+        }
+    }
+
+    private object TypesCompletionProvider : CompletionProvider<CompletionParameters>() {
+        private val keywords = listOf(
+                "Boolean",
+                "Integer",
+                "LongInteger",
+                "Float",
+                "Double",
+                "String",
+                "Object",
+                "Function",
+                "Interface",
+                "Invalid"
+        )
+        override fun addCompletions(parameters: CompletionParameters, context: ProcessingContext, resultSet: CompletionResultSet) {
+            resultSet.addAllElements(listOf(keywords, keywords.map { it.toLowerCase() })
+                    .flatMap { it.map { str -> LookupElementBuilder.create(str) } })
+        }
+    }
+
+    init {
+        extend(CompletionType.BASIC, StandardPatterns.or(psiElement().afterLeaf(psiElement(T_LINE_TERMINATOR)), psiElement().isNull), KeywordCompletionProvider)
+        extend(CompletionType.BASIC, psiElement().afterLeaf(psiElement(T_AS)), TypesCompletionProvider)
+    }
+}

src/main/kotlin/com/interfaced/brs/lang/psi/BrsReference.kt

@@ -88,14 +88,25 @@ class BrsReference(element: BrsElement, textRange: TextRange) : PsiReferenceBase
         val candidates = mutableListOf<PsiElement>()
         val file = element.containingFile
 
-        PsiTreeUtil.treeWalkUp(element, file) { current, _ ->
+        PsiTreeUtil.treeWalkUp(element, file) { current, prev ->
             when (current) {
-                is PsiFile, is BrsForStmt, is BrsFunctionStmt, is BrsAnonFunctionStmtExpr, is BrsSubStmt -> {
-                    val scopeCandidate = resolveInLocalScope(current)
-                    if (scopeCandidate != null) {
-                        candidates.add(scopeCandidate)
-                        false
-                    } else true
+                is PsiFile,
+                is BrsIfStmt,
+                is BrsElseIfStmt,
+                is BrsElseStmt,
+                is BrsForStmt,
+                is BrsFunctionStmt,
+                is BrsWhileStmt,
+                is BrsAnonFunctionStmtExpr,
+                is BrsSubStmt -> {
+                    if (current is BrsIfStmt && (prev is BrsElseIfStmt || prev is BrsElseStmt)) true
+                    else {
+                        val scopeCandidate = resolveInLocalScope(current)
+                        if (scopeCandidate != null) {
+                            candidates.add(scopeCandidate)
+                            false
+                        } else true
+                    }
                 }
                 else -> true
             }

src/main/resources/META-INF/plugin.xml

@@ -31,5 +31,6 @@
         <colorSettingsPage implementation="com.interfaced.brs.ide.colors.BrsColorSettingsPage"/>
         <highlightVisitor implementation="com.interfaced.brs.editor.highlight.BrsHighlighterVisitor"/>
         <elementDescriptionProvider implementation="com.interfaced.brs.lang.BrsDescriptionProvider"/>
+        <completion.contributor language="BrightScript" implementationClass="com.interfaced.brs.lang.completion.BrsCompletionContributor"/>
     </extensions>
 </idea-plugin>