feat: move nil check to call sites

internal/ast/utilities.go

@@ -494,9 +494,9 @@ func isFunctionLikeDeclarationKind(kind Kind) bool {
 }
 
 // Determines if a node is function-like (but is not a signature declaration)
+// ensure node != nil before calling this
 func IsFunctionLikeDeclaration(node *Node) bool {
-	// TODO(rbuckton): Move `node != nil` test to call sites
-	return node != nil && isFunctionLikeDeclarationKind(node.Kind)
+	return isFunctionLikeDeclarationKind(node.Kind)
 }
 
 func isFunctionLikeKind(kind Kind) bool {
@@ -514,9 +514,9 @@ func isFunctionLikeKind(kind Kind) bool {
 }
 
 // Determines if a node is function- or signature-like.
+// Ensure node != nil before calling this
 func IsFunctionLike(node *Node) bool {
-	// TODO(rbuckton): Move `node != nil` test to call sites
-	return node != nil && isFunctionLikeKind(node.Kind)
+	return isFunctionLikeKind(node.Kind)
 }
 
 func IsFunctionLikeOrClassStaticBlockDeclaration(node *Node) bool {
@@ -1064,7 +1064,7 @@ func CanHaveDecorators(node *Node) bool {
 }
 
 func IsFunctionOrModuleBlock(node *Node) bool {
-	return IsSourceFile(node) || IsModuleBlock(node) || IsBlock(node) && IsFunctionLike(node.Parent)
+	return IsSourceFile(node) || IsModuleBlock(node) || IsBlock(node) && node.Parent != nil && IsFunctionLike(node.Parent)
 }
 
 func IsFunctionExpressionOrArrowFunction(node *Node) bool {

internal/binder/binder.go

@@ -2513,7 +2513,7 @@ func GetContainerFlags(node *ast.Node) ContainerFlags {
 	case ast.KindCatchClause, ast.KindForStatement, ast.KindForInStatement, ast.KindForOfStatement, ast.KindCaseBlock:
 		return ContainerFlagsIsBlockScopedContainer | ContainerFlagsHasLocals
 	case ast.KindBlock:
-		if ast.IsFunctionLike(node.Parent) || ast.IsClassStaticBlockDeclaration(node.Parent) {
+		if node.Parent != nil && (ast.IsFunctionLike(node.Parent) || ast.IsClassStaticBlockDeclaration(node.Parent)) {
 			return ContainerFlagsNone
 		} else {
 			return ContainerFlagsIsBlockScopedContainer | ContainerFlagsHasLocals

internal/checker/checker.go

@@ -5534,7 +5534,7 @@ func (c *Checker) checkVarDeclaredNamesNotShadowed(node *ast.Node) {
 				}
 				// names of block-scoped and function scoped variables can collide only
 				// if block scoped variable is defined in the function\module\source file scope (because of variable hoisting)
-				namesShareScope := container != nil && (ast.IsBlock(container) && ast.IsFunctionLike(container.Parent) ||
+				namesShareScope := container != nil && (ast.IsBlock(container) && container.Parent != nil && ast.IsFunctionLike(container.Parent) ||
 					ast.IsModuleBlock(container) || ast.IsModuleDeclaration(container) || ast.IsSourceFile(container))
 				// here we know that function scoped variable is "shadowed" by block scoped one
 				// a var declaration can't hoist past a lexical declaration and it results in a SyntaxError at runtime
@@ -7365,7 +7365,7 @@ func (c *Checker) checkSuperExpression(node *ast.Node) *Type {
 
 func (c *Checker) isInConstructorArgumentInitializer(node *ast.Node, constructorDecl *ast.Node) bool {
 	return ast.FindAncestorOrQuit(node, func(n *ast.Node) ast.FindAncestorResult {
-		if ast.IsFunctionLikeDeclaration(n) {
+		if n != nil && ast.IsFunctionLikeDeclaration(n) {
 			return ast.FindAncestorQuit
 		}
 		if ast.IsParameter(n) && n.Parent == constructorDecl {
@@ -10862,7 +10862,7 @@ func (c *Checker) isUncalledFunctionReference(node *ast.Node, symbol *ast.Symbol
 			return isCallOrNewExpression(parent) && ast.IsIdentifier(node) && c.hasMatchingArgument(parent, node)
 		}
 		return core.Every(symbol.Declarations, func(d *ast.Node) bool {
-			return !ast.IsFunctionLike(d) || c.isDeprecatedDeclaration(d)
+			return d == nil || !ast.IsFunctionLike(d) || c.isDeprecatedDeclaration(d)
 		})
 	}
 	return true
@@ -11128,7 +11128,7 @@ func (c *Checker) isNodeUsedDuringClassInitialization(node *ast.Node) bool {
 	return ast.FindAncestorOrQuit(node, func(element *ast.Node) ast.FindAncestorResult {
 		if ast.IsConstructorDeclaration(element) && ast.NodeIsPresent(element.Body()) || ast.IsPropertyDeclaration(element) {
 			return ast.FindAncestorTrue
-		} else if ast.IsClassLike(element) || ast.IsFunctionLikeDeclaration(element) {
+		} else if ast.IsClassLike(element) || (element != nil && ast.IsFunctionLikeDeclaration(element)) {
 			return ast.FindAncestorQuit
 		}
 		return ast.FindAncestorFalse
@@ -11305,7 +11305,7 @@ func (c *Checker) tryGetThisTypeAt(node *ast.Node) *Type {
 }
 
 func (c *Checker) tryGetThisTypeAtEx(node *ast.Node, includeGlobalThis bool, container *ast.Node) *Type {
-	if ast.IsFunctionLike(container) && (!c.isInParameterInitializerBeforeContainingFunction(node) || getThisParameter(container) != nil) {
+	if container != nil && ast.IsFunctionLike(container) && (!c.isInParameterInitializerBeforeContainingFunction(node) || getThisParameter(container) != nil) {
 		thisType := c.getThisTypeOfDeclaration(container)
 		// Note: a parameter initializer should refer to class-this unless function-this is explicitly annotated.
 		// If this is a function in a JS file, it might be a class method.
@@ -17983,7 +17983,7 @@ func (c *Checker) getSignaturesOfSymbol(symbol *ast.Symbol) []*Signature {
 	}
 	var result []*Signature
 	for i, decl := range symbol.Declarations {
-		if !ast.IsFunctionLike(decl) {
+		if decl == nil || !ast.IsFunctionLike(decl) {
 			continue
 		}
 		// Don't include signature if node is the implementation of an overloaded function. A node is considered
@@ -18582,7 +18582,7 @@ func (c *Checker) createGeneratorType(yieldType *Type, returnType *Type, nextTyp
 
 func (c *Checker) reportErrorsFromWidening(declaration *ast.Node, t *Type, wideningKind WideningKind) {
 	if c.noImplicitAny && t.objectFlags&ObjectFlagsContainsWideningType != 0 {
-		if wideningKind == WideningKindNormal || ast.IsFunctionLikeDeclaration(declaration) && c.shouldReportErrorsFromWideningWithContextualSignature(declaration, wideningKind) {
+		if wideningKind == WideningKindNormal || declaration != nil && ast.IsFunctionLikeDeclaration(declaration) && c.shouldReportErrorsFromWideningWithContextualSignature(declaration, wideningKind) {
 			// Report implicit any error within type if possible, otherwise report error on declaration
 			if !c.reportWideningErrorsInType(t) {
 				c.reportImplicitAny(declaration, t, wideningKind)
@@ -28988,7 +28988,7 @@ func (c *Checker) getSymbolAtLocation(node *ast.Node, ignoreErrors bool) *ast.Sy
 		fallthrough
 	case ast.KindThisKeyword:
 		container := c.getThisContainer(node, false /*includeArrowFunctions*/, false /*includeClassComputedPropertyName*/)
-		if ast.IsFunctionLike(container) {
+		if container != nil && ast.IsFunctionLike(container) {
 			sig := c.getSignatureFromDeclaration(container)
 			if sig.thisParameter != nil {
 				return sig.thisParameter

internal/checker/flow.go

@@ -2166,7 +2166,7 @@ func (c *Checker) hasTypePredicateOrNeverReturnType(sig *Signature) bool {
 
 func (c *Checker) getExplicitThisType(node *ast.Node) *Type {
 	container := ast.GetThisContainer(node, false /*includeArrowFunctions*/, false /*includeClassComputedPropertyName*/)
-	if ast.IsFunctionLike(container) {
+	if container != nil && ast.IsFunctionLike(container) {
 		signature := c.getSignatureFromDeclaration(container)
 		if signature.thisParameter != nil {
 			return c.getExplicitTypeOfSymbol(signature.thisParameter, nil)

internal/checker/grammarchecks.go

@@ -294,7 +294,7 @@ func (c *Checker) checkGrammarModifiers(node *ast.Node /*Union[HasModifiers, Has
 				parent := node.Parent
 
 				if node.Kind == ast.KindTypeParameter {
-					if !(ast.IsFunctionLikeDeclaration(parent) || ast.IsClassLike(parent) ||
+					if !((parent != nil && ast.IsFunctionLikeDeclaration(parent)) || ast.IsClassLike(parent) ||
 						ast.IsFunctionTypeNode(parent) || ast.IsConstructorTypeNode(parent) ||
 						ast.IsCallSignatureDeclaration(parent) || ast.IsConstructSignatureDeclaration(parent) ||
 						ast.IsMethodSignatureDeclaration(parent)) {
@@ -2061,7 +2061,7 @@ func (c *Checker) checkGrammarStatementInAmbientContext(node *ast.Node) bool {
 	if node.Flags&ast.NodeFlagsAmbient != 0 {
 		// Find containing block which is either Block, ModuleBlock, SourceFile
 		links := c.nodeLinks.Get(node)
-		if !links.hasReportedStatementInAmbientContext && (ast.IsFunctionLike(node.Parent) || ast.IsAccessor(node.Parent)) {
+		if !links.hasReportedStatementInAmbientContext && (node.Parent != nil && ast.IsFunctionLike(node.Parent) || ast.IsAccessor(node.Parent)) {
 			links.hasReportedStatementInAmbientContext = c.grammarErrorOnFirstToken(node, diagnostics.An_implementation_cannot_be_declared_in_ambient_contexts)
 			return links.hasReportedStatementInAmbientContext
 		}