EA-105522, KT-20256: Fix TextRange.<init> "Invalid range specified"

Check when caret inside template, and don't try to create invalid
range then

 EA-105522 fixed
 #KT-20256 fixed

idea/idea-completion/src/org/jetbrains/kotlin/idea/completion/confidence/EnableAutopopupInStringTemplate.kt

@@ -25,10 +25,15 @@ import org.jetbrains.kotlin.psi.KtSimpleNameStringTemplateEntry
 import org.jetbrains.kotlin.psi.psiUtil.endOffset
 import org.jetbrains.kotlin.psi.psiUtil.getParentOfType
 import org.jetbrains.kotlin.psi.psiUtil.prevLeaf
+import org.jetbrains.kotlin.psi.psiUtil.startOffset
 
 class EnableAutopopupInStringTemplate : CompletionConfidence() {
     override fun shouldSkipAutopopup(contextElement: PsiElement, psiFile: PsiFile, offset: Int): ThreeState {
         val stringTemplate = contextElement.prevLeaf()?.getParentOfType<KtSimpleNameStringTemplateEntry>(strict = false) ?: return ThreeState.UNSURE
+
+        // "$<caret>nameRef" stringTemplate here is "$nameRef", so offset are inside template, we should show lookup
+        if (offset in stringTemplate.startOffset until stringTemplate.endOffset) return ThreeState.NO
+
         val textRange = TextRange.create(stringTemplate.endOffset, offset)
         val containsWhitespaces = textRange.substring(psiFile.text).any { it.isWhitespace() }
         return if (containsWhitespaces) ThreeState.UNSURE else ThreeState.NO

idea/idea-completion/testData/confidence/AutoPopupInStringTemplateAfterDollar.kt

@@ -0,0 +1,7 @@
+
+fun foo() {
+    val aaa = ""
+    val y = "$a<caret>aaa"
+}
+
+// ELEMENT: aaa

idea/idea-completion/tests/org/jetbrains/kotlin/idea/completion/test/confidence/KotlinConfidenceTest.java

@@ -68,6 +68,10 @@ public class KotlinConfidenceTest extends LightCompletionTestCase {
         doTest();
     }
 
+    public void testAutoPopupInStringTemplateAfterDollar() {
+        doTest();
+    }
+
     public void testNoAutoPopupInStringTemplateAfterSpace() {
         doTest();
     }