Fix incorrect ambiguous warning (sqlc-dev#57)

Author: kyleconroy

internal/dinosql/parser.go

@@ -714,15 +714,16 @@ func resolveCatalogRefs(c core.Catalog, rvs []nodes.RangeVar, args []paramRef) (
 					panic("too many field items: " + strconv.Itoa(len(items)))
 				}
 
-				var search []string
-				if table, ok := aliasMap[alias]; ok {
-					search = append(search, table)
-				} else {
-					search = tables
+				search := tables
+				if alias != "" {
+					search = []string{alias}
 				}
 
 				var found int
 				for _, table := range search {
+					if original, ok := aliasMap[table]; ok {
+						table = original
+					}
 					if c, ok := typeMap[table][key]; ok {
 						found += 1
 						a = append(a, Parameter{

internal/dinosql/query_test.go

@@ -257,6 +257,27 @@ func TestQueries(t *testing.T) {
 				Params: []Parameter{{1, core.Column{Name: "id", DataType: "serial", NotNull: true}}},
 			},
 		},
+		{
+			"table-name",
+			`
+			CREATE TABLE bar (id serial not null);
+			CREATE TABLE foo (id serial not null, bar serial references bar(id));
+
+			SELECT foo.id
+			FROM foo
+			JOIN bar ON foo.bar = bar.id
+			WHERE bar.id = $1 AND foo.id = $2;
+			`,
+			Query{
+				Columns: []core.Column{
+					{Name: "id", DataType: "serial", NotNull: true},
+				},
+				Params: []Parameter{
+					{1, core.Column{Name: "id", DataType: "serial", NotNull: true}},
+					{2, core.Column{Name: "id", DataType: "serial", NotNull: true}},
+				},
+			},
+		},
 		{
 			"star",
 			`