fix(golang): Escape reserved keywords (sqlc-dev#2849)

* fix(golang): Escape reserved keywords

Append `_` to variable names that are reserved

Author: kyleconroy

internal/codegen/golang/query.go

@@ -61,15 +61,15 @@ func (v QueryValue) Pairs() []Argument {
 		var out []Argument
 		for _, f := range v.Struct.Fields {
 			out = append(out, Argument{
-				Name: toLowerCase(f.Name),
+				Name: escape(toLowerCase(f.Name)),
 				Type: f.Type,
 			})
 		}
 		return out
 	}
 	return []Argument{
 		{
-			Name: v.Name,
+			Name: escape(v.Name),
 			Type: v.DefineType(),
 		},
 	}
@@ -102,9 +102,9 @@ func (v *QueryValue) DefineType() string {
 
 func (v *QueryValue) ReturnName() string {
 	if v.IsPointer() {
-		return "&" + v.Name
+		return "&" + escape(v.Name)
 	}
-	return v.Name
+	return escape(v.Name)
 }
 
 func (v QueryValue) UniqueFields() []Field {
@@ -129,16 +129,16 @@ func (v QueryValue) Params() string {
 	var out []string
 	if v.Struct == nil {
 		if !v.Column.IsSqlcSlice && strings.HasPrefix(v.Typ, "[]") && v.Typ != "[]byte" && !v.SQLDriver.IsPGX() {
-			out = append(out, "pq.Array("+v.Name+")")
+			out = append(out, "pq.Array("+escape(v.Name)+")")
 		} else {
-			out = append(out, v.Name)
+			out = append(out, escape(v.Name))
 		}
 	} else {
 		for _, f := range v.Struct.Fields {
 			if !f.HasSqlcSlice() && strings.HasPrefix(f.Type, "[]") && f.Type != "[]byte" && !v.SQLDriver.IsPGX() {
-				out = append(out, "pq.Array("+v.VariableForField(f)+")")
+				out = append(out, "pq.Array("+escape(v.VariableForField(f))+")")
 			} else {
-				out = append(out, v.VariableForField(f))
+				out = append(out, escape(v.VariableForField(f)))
 			}
 		}
 	}

internal/codegen/golang/reserved.go

@@ -0,0 +1,65 @@
+package golang
+
+func escape(s string) string {
+	if IsReserved(s) {
+		return s + "_"
+	}
+	return s
+}
+
+func IsReserved(s string) bool {
+	switch s {
+	case "break":
+		return true
+	case "default":
+		return true
+	case "func":
+		return true
+	case "interface":
+		return true
+	case "select":
+		return true
+	case "case":
+		return true
+	case "defer":
+		return true
+	case "go":
+		return true
+	case "map":
+		return true
+	case "struct":
+		return true
+	case "chan":
+		return true
+	case "else":
+		return true
+	case "goto":
+		return true
+	case "package":
+		return true
+	case "switch":
+		return true
+	case "const":
+		return true
+	case "fallthrough":
+		return true
+	case "if":
+		return true
+	case "range":
+		return true
+	case "type":
+		return true
+	case "continue":
+		return true
+	case "for":
+		return true
+	case "import":
+		return true
+	case "return":
+		return true
+	case "var":
+		return true
+	default:
+		return false
+	}
+}

internal/codegen/golang/result.go

@@ -215,7 +215,7 @@ func buildQueries(req *plugin.CodeGenRequest, options *opts, structs []Struct) (
 		if len(query.Params) == 1 && qpl != 0 {
 			p := query.Params[0]
 			gq.Arg = QueryValue{
-				Name:      paramName(p),
+				Name:      escape(paramName(p)),
 				DBName:    p.Column.GetName(),
 				Typ:       goType(req, options, p.Column),
 				SQLDriver: sqlpkg,
@@ -251,7 +251,7 @@ func buildQueries(req *plugin.CodeGenRequest, options *opts, structs []Struct) (
 			name := columnName(c, 0)
 			name = strings.Replace(name, "$", "_", -1)
 			gq.Ret = QueryValue{
-				Name:      name,
+				Name:      escape(name),
 				DBName:    name,
 				Typ:       goType(req, options, c),
 				SQLDriver: sqlpkg,

internal/endtoend/testdata/params_go_keywords/issue.md

@@ -0,0 +1 @@
+# TODO