handling of dollar signs in function names by removing the char from codegen output (#1359)

adding a e2e case

Author: Nlossae

internal/codegen/golang/result.go

@@ -193,8 +193,12 @@ func buildQueries(r *compiler.Result, settings config.CombinedSettings, structs
 
 		if len(query.Columns) == 1 {
 			c := query.Columns[0]
+			name := columnName(c, 0)
+			if c.IsFuncCall {
+				name = strings.Replace(name, "$", "_", -1)
+			}
 			gq.Ret = QueryValue{
-				Name:       columnName(c, 0),
+				Name:       name,
 				Typ:        goType(r, c, settings),
 				SQLPackage: sqlpkg,
 			}

internal/compiler/output_columns.go

@@ -210,9 +210,18 @@ func outputColumns(qc *QueryCatalog, node ast.Node) ([]*Column, error) {
 			}
 			fun, err := qc.catalog.ResolveFuncCall(n)
 			if err == nil {
-				cols = append(cols, &Column{Name: name, DataType: dataType(fun.ReturnType), NotNull: !fun.ReturnTypeNullable})
+				cols = append(cols, &Column{
+					Name:       name,
+					DataType:   dataType(fun.ReturnType),
+					NotNull:    !fun.ReturnTypeNullable,
+					IsFuncCall: true,
+				})
 			} else {
-				cols = append(cols, &Column{Name: name, DataType: "any"})
+				cols = append(cols, &Column{
+					Name:       name,
+					DataType:   "any",
+					IsFuncCall: true,
+				})
 			}
 
 		case *ast.SubLink:

internal/compiler/query.go

@@ -22,6 +22,7 @@ type Column struct {
 	Comment      string
 	Length       *int
 	IsNamedParam bool
+	IsFuncCall   bool
 
 	// XXX: Figure out what PostgreSQL calls `foo.id`
 	Scope      string

internal/endtoend/testdata/identifier_dollar_sign/db/db.go

@@ -0,0 +1,4 @@
+CREATE FUNCTION f$n() RETURNS integer AS 'SELECT 1';
+
+-- name: Fn :one
+SELECT f$n();

internal/endtoend/testdata/identifier_dollar_sign/db/models.go

@@ -0,0 +1,11 @@
+{
+  "version": "1",
+  "packages": [
+    {
+      "path": "db",
+      "engine": "postgresql",
+      "schema": "query.sql",
+      "queries": "query.sql"
+    }
+  ]
+}