fix(compiler): Respect alias name for coalesce (#1232)

Author: kyleconroy

internal/compiler/output_columns.go

@@ -127,6 +127,10 @@ func outputColumns(qc *QueryCatalog, node ast.Node) ([]*Column, error) {
 			}
 
 		case *ast.CoalesceExpr:
+			name := "coalesce"
+			if res.Name != nil {
+				name = *res.Name
+			}
 			var found bool
 			for _, arg := range n.Args.Items {
 				if found {
@@ -146,7 +150,7 @@ func outputColumns(qc *QueryCatalog, node ast.Node) ([]*Column, error) {
 				}
 			}
 			if !found {
-				cols = append(cols, &Column{Name: "coalesce", DataType: "any", NotNull: false})
+				cols = append(cols, &Column{Name: name, DataType: "any", NotNull: false})
 			}
 
 		case *ast.ColumnRef:

internal/endtoend/testdata/coalesce_as/mysql/go/db.go

@@ -0,0 +1,9 @@
+CREATE TABLE foo (
+    bar text,
+    baz integer
+);
+
+-- name: SumBaz :many
+SELECT bar, coalesce(sum(baz), 0) as quantity
+FROM foo
+GROUP BY 1;

internal/endtoend/testdata/coalesce_as/mysql/go/models.go

@@ -0,0 +1,12 @@
+{
+  "version": "1",
+  "packages": [
+    {
+      "path": "go",
+      "engine": "mysql",
+      "name": "querytest",
+      "schema": "query.sql",
+      "queries": "query.sql"
+    }
+  ]
+}

internal/endtoend/testdata/coalesce_as/mysql/go/query.sql.go

@@ -0,0 +1,9 @@
+CREATE TABLE foo (
+    bar text,
+    baz bigint
+);
+
+-- name: SumBaz :many
+SELECT bar, coalesce(sum(baz), 0) as quantity
+FROM foo
+GROUP BY 1;