fix: response content-type matching should be per-status code

Author: vwong

src/__tests__/fixtures/response-header/baseline.json

@@ -140,7 +140,7 @@
     "code": "response.content-type.incompatible",
     "message": "Response Content-Type header is incompatible with the mime-types the spec defines to produce",
     "mockDetails": {
-      "interactionDescription": "should error on unknown response content type",
+      "interactionDescription": "should error on unknown response content type, per status code",
       "interactionState": "[none]",
       "location": "[root].interactions[6].response.headers.Content-Type",
       "value": "text/html"

src/__tests__/fixtures/response-header/oas.yaml

@@ -26,6 +26,11 @@ paths:
           content:
             application/json:
               schema: {}
+        "201":
+          description: OK
+          content:
+            text/html:
+              schema: {}
   /delete:
     delete:
       responses:

src/__tests__/fixtures/response-header/pact.json

@@ -86,7 +86,7 @@
       }
     },
     {
-      "description": "should error on unknown response content type",
+      "description": "should error on unknown response content type, per status code",
       "request": {
         "method": "GET",
         "path": "/different-response-types"

src/__tests__/fixtures/response-header/results.json

@@ -87,7 +87,7 @@
     "code": "response.content-type.incompatible",
     "message": "Response Content-Type header is incompatible with the mime-types the spec defines to produce",
     "mockDetails": {
-      "interactionDescription": "should error on unknown response content type",
+      "interactionDescription": "should error on unknown response content type, per status code",
       "interactionState": "[none]",
       "location": "[root].interactions[6].response.headers.content-type",
       "value": "text/html"

src/compare/responseHeader.ts

@@ -24,17 +24,6 @@ export function* compareResHeader(
 ): Iterable<Result> {
   const { method, oas, operation, path } = route.store;
 
-  const allAvailableResponseContentTypes =
-    operation.produces ||
-    Object.entries(operation.responses).reduce(
-      (acc: string[], [_status, response]) => {
-        return [
-          ...acc,
-          ...Object.keys(dereferenceOas(response || {}, oas)?.content || {}),
-        ];
-      },
-      [],
-    );
   const availableResponseContentType =
     operation.produces ||
     Object.keys(
@@ -59,7 +48,7 @@ export function* compareResHeader(
   const responseContentType =
     responseHeaders.get("content-type")?.split(";")[0] || "";
 
-  if (responseContentType && !allAvailableResponseContentTypes.length) {
+  if (responseContentType && !availableResponseContentType.length) {
     yield {
       code: "response.content-type.unknown",
       message: