Panic during code generation when using builder style interface + object in query parameters

[ollyswanson]

Sorry for not putting together something to reproduce the issue:

I'm using the builder-style interface; an OpenAPI spec that I don't control has been updated to specify its query parameters as an object.

I'm hitting a panic here:

progenitor/progenitor-impl/src/method.rs

Lines 1576 to 1588 in 9d88d24

	// For builder-capable bodies we offer a `body()`
	// method that sets the full body (by constructing
	// a builder **from** the body type). We also offer
	// a `body_map()` method that operates on the
	// builder itself.
	(Some(builder_name), false) => {
	assert_eq!(param.name, "body");
	let typ = ty.ident();
	let err_msg = format!(
	"conversion to `{}` for {} failed: {{}}",
	ty.name(),
	param.name,
	);

Message:  assertion `left == right` failed
  left: "my_object"
 right: "body"

I've tried patching the code generation locally to parameterize the codegen in this branch + remove the assertion - but I haven't had the time to understand the surrounding code yet (and if there's a reason for the assertion beyond "we don't expect any builders that aren't for the body").

Is this just a case of not having implemented #1017 at the time the assertion was written?

The fix appears to be relatively straightforward but I'm struggling to get the time to think it through/follow it through - I just wanted to make sure that I wasn't missing something obvious.

[ahl]

Are you able to share the input OpenAPI?

[ollyswanson]

I'm not able to share the exact spec - but I've spent a few mins reproducing it by recreating the problematic portion of the spec.

{
  "openapi": "3.0.3",
  "info": {
    "title": "Reproducer",
    "version": "2.3.0"
  },
  "security": [
    {
      "apikey": []
    }
  ],
  "paths": {
    "/reproducer": {
      "get": {
        "tags": ["reproduction"],
        "summary": "Reproduction",
        "description": "Reproduction",
        "operationId": "getReproduction",
        "parameters": [
          {
            "name": "params",
            "in": "query",
            "required": true,
            "schema": {
              "$ref": "#/components/schemas/ReproParams"
            }
          }
        ],
        "responses": {
          "200": {
            "description": "OK",
            "content": {
              "text/plain": {
                "schema": {
                  "type": "string"
                }
              }
            }
          }
        }
      }
    }
  },
  "components": {
    "schemas": {
      "ReproParams": {
        "type": "object",
        "properties": {
          "foo": {
            "type": "string"
          },
          "bar": {
            "type": "string"
          }
        }
      }
    }
  }
}

When I generate this with

    let mut generator = Generator::new(
        GenerationSettings::default()
            .with_tag(TagStyle::Separate)
            .with_interface(InterfaceStyle::Positional),
    );

I hit the panic.

When I generate it with

    let mut generator =
        Generator::new(GenerationSettings::default().with_interface(InterfaceStyle::Positional));

It generates the code as expected.