From 007ac71fdf2f42d1ae3cba93fdf07c10c8e0a080 Mon Sep 17 00:00:00 2001
From: Jamie Wilkinson <jaq@spacepants.org>
Date: Wed, 13 Aug 2025 13:51:14 +1000
Subject: [PATCH 1/2] feat: Support more filetypes in the output_format.

`cue help filetypes` describes a lot more filetypes we can use for output.

I am trying to generate OpenAPI YAML specs from Cue, per https://cuelang.org/docs/concept/how-cue-works-with-openapi/ and seem to be getting something useful when I add the `openapi+yaml` output format, supported by this change.
---
 cue/cue.bzl | 31 ++++++++++++++++++-------------
 1 file changed, 18 insertions(+), 13 deletions(-)

diff --git a/cue/cue.bzl b/cue/cue.bzl
index f73c4a8..5e490e0 100644
--- a/cue/cue.bzl
+++ b/cue/cue.bzl
@@ -623,6 +623,22 @@ def _augment_consolidated_output_args(ctx, args):
         args.add("--inline-imports")
     args.add("--out", ctx.attr.output_format)
 
+# https://cuelang.org/docs/reference/command/cue-help-filetypes/
+extension_by_filetype = {
+    "cue": "cue",
+    "json": "json",
+    "yaml": "yaml",
+    "toml": "toml",
+    "jsonl": "jsonl",
+    "jsonschema+json": "json",
+    "openapi+yaml", "yaml",
+    "proto": "proto",
+    "pb+proto": "proto",
+    "textproto": "textproto",
+    "go": "go",
+    # binary not yet supported
+}
+    
 def _add_common_consolidated_output_attrs_to(attrs):
     attrs.update({
         "inline_imports": attr.bool(
@@ -632,12 +648,7 @@ def _add_common_consolidated_output_attrs_to(attrs):
         "output_format": attr.string(
             doc = "Output format",
             default = "cue",
-            values = [
-                "cue",
-                "json",
-                "text",
-                "yaml",
-            ],
+            values = extension_by_filetype.keys(),
         ),
         "result": attr.output(
             doc = """The built result in the format specified in the "output_format" attribute.""",
@@ -647,14 +658,8 @@ def _add_common_consolidated_output_attrs_to(attrs):
     return attrs
 
 def _prepare_consolidated_output_rule(name, **kwargs):
-    extension_by_format = {
-        "cue": "cue",
-        "json": "json",
-        "text": "txt",
-        "yaml": "yaml",
-    }
     output_format = kwargs.get("output_format", "cue")
-    result = kwargs.pop("result", name + "." + extension_by_format[output_format])
+    result = kwargs.pop("result", name + "." + extension_by_filetype[output_format])
     return kwargs | {
         "result": result,
     }

From 35430ada372370c69f793771299e910151684da3 Mon Sep 17 00:00:00 2001
From: Jamie Wilkinson <jaq@spacepants.org>
Date: Wed, 13 Aug 2025 15:42:24 +1000
Subject: [PATCH 2/2] fix: Support export as well as def.

---
 cue/cue.bzl | 15 ++-------------
 1 file changed, 2 insertions(+), 13 deletions(-)

diff --git a/cue/cue.bzl b/cue/cue.bzl
index 5e490e0..385f25a 100644
--- a/cue/cue.bzl
+++ b/cue/cue.bzl
@@ -798,12 +798,7 @@ def _add_common_exported_output_attrs_to(attrs):
         "output_format": attr.string(
             doc = "Output format",
             default = "json",
-            values = [
-                "cue",
-                "json",
-                "text",
-                "yaml",
-            ],
+            values = extension_by_filetype.keys(),
         ),
         "result": attr.output(
             doc = """The built result in the format specified in the "output_format" attribute.""",
@@ -813,14 +808,8 @@ def _add_common_exported_output_attrs_to(attrs):
     return attrs
 
 def _prepare_exported_output_rule(name, **kwargs):
-    extension_by_format = {
-        "cue": "cue",
-        "json": "json",
-        "text": "txt",
-        "yaml": "yaml",
-    }
     output_format = kwargs.get("output_format", "json")
-    result = kwargs.pop("result", name + "." + extension_by_format[output_format])
+    result = kwargs.pop("result", name + "." + extension_by_filetype[output_format])
     return kwargs | {
         "result": result,
     }