vendor tsgo

tools/tsgo/internal/ls/lsutil/asi.go

@@ -0,0 +1,104 @@
+package lsutil
+
+import (
+	"github.com/microsoft/typescript-go/internal/ast"
+	"github.com/microsoft/typescript-go/internal/astnav"
+	"github.com/microsoft/typescript-go/internal/scanner"
+)
+
+func PositionIsASICandidate(pos int, context *ast.Node, file *ast.SourceFile) bool {
+	contextAncestor := ast.FindAncestorOrQuit(context, func(ancestor *ast.Node) ast.FindAncestorResult {
+		if ancestor.End() != pos {
+			return ast.FindAncestorQuit
+		}
+
+		return ast.ToFindAncestorResult(SyntaxMayBeASICandidate(ancestor.Kind))
+	})
+
+	return contextAncestor != nil && NodeIsASICandidate(contextAncestor, file)
+}
+
+func SyntaxMayBeASICandidate(kind ast.Kind) bool {
+	return SyntaxRequiresTrailingCommaOrSemicolonOrASI(kind) ||
+		SyntaxRequiresTrailingFunctionBlockOrSemicolonOrASI(kind) ||
+		SyntaxRequiresTrailingModuleBlockOrSemicolonOrASI(kind) ||
+		SyntaxRequiresTrailingSemicolonOrASI(kind)
+}
+
+func SyntaxRequiresTrailingCommaOrSemicolonOrASI(kind ast.Kind) bool {
+	return kind == ast.KindCallSignature ||
+		kind == ast.KindConstructSignature ||
+		kind == ast.KindIndexSignature ||
+		kind == ast.KindPropertySignature ||
+		kind == ast.KindMethodSignature
+}
+
+func SyntaxRequiresTrailingFunctionBlockOrSemicolonOrASI(kind ast.Kind) bool {
+	return kind == ast.KindFunctionDeclaration ||
+		kind == ast.KindConstructor ||
+		kind == ast.KindMethodDeclaration ||
+		kind == ast.KindGetAccessor ||
+		kind == ast.KindSetAccessor
+}
+
+func SyntaxRequiresTrailingModuleBlockOrSemicolonOrASI(kind ast.Kind) bool {
+	return kind == ast.KindModuleDeclaration
+}
+
+func SyntaxRequiresTrailingSemicolonOrASI(kind ast.Kind) bool {
+	return kind == ast.KindVariableStatement ||
+		kind == ast.KindExpressionStatement ||
+		kind == ast.KindDoStatement ||
+		kind == ast.KindContinueStatement ||
+		kind == ast.KindBreakStatement ||
+		kind == ast.KindReturnStatement ||
+		kind == ast.KindThrowStatement ||
+		kind == ast.KindDebuggerStatement ||
+		kind == ast.KindPropertyDeclaration ||
+		kind == ast.KindTypeAliasDeclaration ||
+		kind == ast.KindImportDeclaration ||
+		kind == ast.KindImportEqualsDeclaration ||
+		kind == ast.KindExportDeclaration ||
+		kind == ast.KindNamespaceExportDeclaration ||
+		kind == ast.KindExportAssignment
+}
+
+func NodeIsASICandidate(node *ast.Node, file *ast.SourceFile) bool {
+	lastToken := GetLastToken(node, file)
+	if lastToken != nil && lastToken.Kind == ast.KindSemicolonToken {
+		return false
+	}
+
+	if SyntaxRequiresTrailingCommaOrSemicolonOrASI(node.Kind) {
+		if lastToken != nil && lastToken.Kind == ast.KindCommaToken {
+			return false
+		}
+	} else if SyntaxRequiresTrailingModuleBlockOrSemicolonOrASI(node.Kind) {
+		lastChild := GetLastChild(node, file)
+		if lastChild != nil && ast.IsModuleBlock(lastChild) {
+			return false
+		}
+	} else if SyntaxRequiresTrailingFunctionBlockOrSemicolonOrASI(node.Kind) {
+		lastChild := GetLastChild(node, file)
+		if lastChild != nil && ast.IsFunctionBlock(lastChild) {
+			return false
+		}
+	} else if !SyntaxRequiresTrailingSemicolonOrASI(node.Kind) {
+		return false
+	}
+
+	// See comment in parser's `parseDoStatement`
+	if node.Kind == ast.KindDoStatement {
+		return true
+	}
+
+	topNode := ast.FindAncestor(node, func(ancestor *ast.Node) bool { return ancestor.Parent == nil })
+	nextToken := astnav.FindNextToken(node, topNode, file)
+	if nextToken == nil || nextToken.Kind == ast.KindCloseBraceToken {
+		return true
+	}
+
+	startLine := scanner.GetECMALineOfPosition(file, node.End())
+	endLine := scanner.GetECMALineOfPosition(file, astnav.GetStartOfNode(nextToken, file, false /*includeJSDoc*/))
+	return startLine != endLine
+}