fix null ptr issues (#182)

Author: patricklx

src/main/kotlin/com/emberjs/hbs/HbsLocalReference.kt

@@ -9,6 +9,8 @@ import com.emberjs.psi.EmberNamedAttribute
 import com.emberjs.psi.EmberNamedElement
 import com.emberjs.refactoring.SimpleNodeFactory
 import com.emberjs.utils.EmberUtils
+import com.emberjs.utils.ifFalse
+import com.emberjs.utils.ifTrue
 import com.emberjs.utils.originalVirtualFile
 import com.emberjs.xml.EmberAttrDec
 import com.intellij.injected.editor.VirtualFileWindow
@@ -26,6 +28,7 @@ import com.intellij.lang.javascript.psi.impl.JSVariableImpl
 import com.intellij.lang.javascript.psi.jsdoc.impl.JSDocCommentImpl
 import com.intellij.lang.javascript.psi.resolve.JSContextResolver
 import com.intellij.lang.javascript.psi.types.JSRecordTypeImpl
+import com.intellij.lang.javascript.psi.types.recordImpl.PropertySignatureImpl
 import com.intellij.openapi.util.TextRange
 import com.intellij.psi.*
 import com.intellij.psi.css.CssRulesetList
@@ -329,7 +332,12 @@ class HbsLocalReference(private val leaf: PsiElement, val resolved: Any?) : HbRe
                     }
                 }
             }
-            val followed = EmberUtils.followReferences(any as PsiElement?)
+
+            if (any is PropertySignatureImpl) {
+                return resolveToJs(any.memberSource.singleElement, path.subList(1, max(path.lastIndex, 1)), resolveIncomplete, recursionCounter + 1)
+            }
+
+            val followed = (any as? PsiElement?)?.let { EmberUtils.followReferences(it) } ?: any
             if (followed !== null && followed != any) {
                 return resolveToJs(followed, path, resolveIncomplete, recursionCounter + 1)
             }
@@ -382,9 +390,14 @@ class HbsLocalReference(private val leaf: PsiElement, val resolved: Any?) : HbRe
         }
 
         fun findReference(element: PsiElement): PsiReference? {
-            val psiFile = PsiManager.getInstance(element.project).findFile(element.originalVirtualFile!!)
-            val document = PsiDocumentManager.getInstance(element.project).getDocument(psiFile!!)!!
-            val service = GlintLanguageServiceProvider(element.project).getService(element.originalVirtualFile!!)
+            var isValid = element.originalVirtualFile?.isValid.ifTrue { true }
+            val psiFile = isValid?.let { PsiManager.getInstance(element.project).findFile(element.originalVirtualFile!!) }
+            isValid = isValid?.and(psiFile != null).ifTrue { true }
+            val document = isValid?.let { PsiDocumentManager.getInstance(element.project).getDocument(psiFile!!) }
+            isValid = isValid?.and(document != null).ifTrue { true }
+            val service = isValid?.let {
+                GlintLanguageServiceProvider(element.project).getService(element.originalVirtualFile!!)
+            }
 
             val name = element.text.replace("IntellijIdeaRulezzz", "")
 
@@ -415,15 +428,15 @@ class HbsLocalReference(private val leaf: PsiElement, val resolved: Any?) : HbRe
                 val yieldRef = (ref as? HbsLocalReference)?.resolveYield()
                 if (yieldRef != null) {
                     val res = resolveToJs(yieldRef, listOf(element.text))
-                    return HbsLocalReference(element, res ?: service?.getNavigationFor(document, element, true)?.firstOrNull()?.parent)
+                    return HbsLocalReference(element, res ?: service?.getNavigationFor(document!!, element, true)?.firstOrNull()?.parent)
                 }
                 val sig = (ref as? HbsLocalReference)?.resolved as? JSRecordType.PropertySignature
                 if (ref != null && resolveToJs(sig ?: ref.resolve(), listOf(element.text)) != null) {
                     return HbsLocalReference(element, resolveToJs(sig ?: ref.resolve(), listOf(element.text)))
                 }
                 val ref2 = sibling.references.find { it is HbReference } as HbReference?
                 val res = resolveToJs(ref2?.resolve(), listOf(element.text))
-                return HbsLocalReference(element, res ?: service?.getNavigationFor(document, element, true)?.firstOrNull()?.parent)
+                return HbsLocalReference(element, res ?: service?.getNavigationFor(document!!, element, true)?.firstOrNull()?.parent)
             }
 
             if (element.parent is HbData) {
@@ -438,7 +451,7 @@ class HbsLocalReference(private val leaf: PsiElement, val resolved: Any?) : HbRe
                         val modelProp = (cls as? JSClass)?.let { it.jsType.asRecordType().properties.find { it.memberName == "model" } }
                         return modelProp?.let { HbsLocalReference(element, it.memberSource.singleElement) }
                     }
-                    val resolved = service?.getNavigationFor(document, element, true)?.firstOrNull()?.parent
+                    val resolved = service?.getNavigationFor(document!!, element, true)?.firstOrNull()?.parent
                     return resolved?.let { HbsLocalReference(element, it) }
                 }
             }
@@ -463,7 +476,7 @@ class HbsLocalReference(private val leaf: PsiElement, val resolved: Any?) : HbRe
             return referenceBlocks(element, name)
                     ?: resolveToLocalJs(element)
                     ?: let {
-                        val resolved = service?.getNavigationFor(document, element, true)?.firstOrNull()?.parent
+                        val resolved = service?.getNavigationFor(document!!, element, true)?.firstOrNull()?.parent
                         resolved?.let { HbsLocalReference(element, it) }
                     }
         }

src/main/kotlin/com/emberjs/utils/BooleanExt.kt

@@ -20,4 +20,4 @@ inline fun  <R> Boolean?.ifFalse(block: Boolean?.() -> R): R? {
     }
 
     return null
-}
+}