Go: add isParenthesized relation to keep track of parentheses around expressions

go/downgrades/b4012cfa6fa7de1878c247155b7dfcd76df2604d/upgrade.properties

@@ -0,0 +1,3 @@
+description: Remove table recording the number of parentheses around expressions
+compatibility: full
+isParenthesized.rel: delete

go/extractor/dbscheme/dbscheme.go

@@ -415,17 +415,19 @@ func AddDefaultSnippet(snippet string) bool {
 
 // PrintDbScheme prints the schema of this database to the writer `w`
 func PrintDbScheme(w io.Writer) {
-	fmt.Fprintf(w, "/** Auto-generated dbscheme; do not edit. Run `make gen` in directory `go/` to regenerate. */\n\n")
+	var b strings.Builder
+	fmt.Fprintf(&b, "/** Auto-generated dbscheme; do not edit. Run `make gen` in directory `go/` to regenerate. */\n\n")
 	for _, snippet := range defaultSnippets {
-		fmt.Fprintf(w, "%s\n", snippet)
+		fmt.Fprintf(&b, "%s\n", snippet)
 	}
 	for _, table := range tables {
-		fmt.Fprintf(w, "%s\n\n", table.String())
+		fmt.Fprintf(&b, "%s\n\n", table.String())
 	}
 	for _, tp := range types {
 		def := tp.def()
 		if def != "" {
-			fmt.Fprintf(w, "%s\n\n", def)
+			fmt.Fprintf(&b, "%s\n\n", def)
 		}
 	}
+	fmt.Fprintln(w, strings.TrimRight(b.String(), "\n"))
 }

go/extractor/dbscheme/tables.go

@@ -996,6 +996,12 @@ var ExprsTable = NewTable("exprs",
 	IntColumn("idx"),
 ).KeySet("parent", "idx")
 
+// IsParenthesizedTable is the table associating expressions with how many parentheses they originally had
+var IsParenthesizedTable = NewTable("isParenthesized",
+	EntityColumn(ExprType, "id").Unique(),
+	IntColumn("parentheses"),
+)
+
 // LiteralsTable is the table associating literal expression AST nodes with their values
 var LiteralsTable = NewTable("literals",
 	EntityColumn(ExprType, "expr").Unique(),

go/extractor/extractor.go

@@ -1026,12 +1026,22 @@ func extractExpr(tw *trap.Writer, expr ast.Expr, parent trap.Label, idx int, ski
 	}
 
 	// Skip parenthesised expressions and extract their child directly in their place
-	if paren, ok := expr.(*ast.ParenExpr); ok {
-		extractExpr(tw, paren.X, parent, idx, skipExtractingValue)
-		return
+	nParens := 0
+	for {
+		paren, ok := expr.(*ast.ParenExpr)
+		if !ok {
+			break
+		}
+		nParens++
+		expr = paren.X
 	}
 
 	lbl := tw.Labeler.LocalID(expr)
+
+	if nParens > 0 {
+		dbscheme.IsParenthesizedTable.Emit(tw, lbl, nParens)
+	}
+
 	extractTypeOf(tw, expr, lbl)
 
 	var kind int

go/ql/lib/go.dbscheme

@@ -162,6 +162,8 @@ doc_comments(unique int node: @documentable ref, int comment: @comment_group ref
 #keyset[parent, idx]
 exprs(unique int id: @expr, int kind: int ref, int parent: @exprparent ref, int idx: int ref);
 
+isParenthesized(unique int id: @expr ref, int parentheses: int ref);
+
 literals(unique int expr: @expr ref, string value: string ref, string raw: string ref);
 
 constvalues(unique int expr: @expr ref, string value: string ref, string exact: string ref);
@@ -561,4 +563,3 @@ case @error.kind of
 | 1 = @listerror
 | 2 = @parseerror
 | 3 = @typeerror;
-