Add information on development for MacOS contributors. (#214)

Dockerfile.test

@@ -0,0 +1,6 @@
+FROM golang:1.21
+WORKDIR /work
+COPY go.* .
+RUN go mod download
+COPY . .
+RUN --mount=type=cache,target=/root/.cache/go-build make test

Makefile

@@ -41,6 +41,10 @@ build:
 test: build
 	go test -cover ./...
 
+.PHONY: test-in-docker
+test-in-docker:
+	docker build -f Dockerfile.test --progress plain .
+
 .PHONY: lint-structs
 lint-structs:
 	@golangci-lint run --enable exhaustruct ./cmd --tests=false || \

README.md

@@ -90,6 +90,7 @@ contexts:
 ```
 
 Optional you can specify `issuer_type: generic` if you use other issuers as Dex, e.g. Keycloak (this will request scopes `openid,profile,email`):
+
 ```bash
 contexts:
   prod:
@@ -101,6 +102,7 @@ contexts:
 ```
 
 If you must specify special scopes for your issuer, you can use `custom_scopes`:
+
 ```bash
 contexts:
   prod:
@@ -118,3 +120,9 @@ Full documentation is generated out of the cobra command implementation with:
 `metalctl markdown`
 
 generated markdown is [here](docs/metalctl.md) and [here](https://docs.metal-stack.io/stable/external/metalctl/README/)
+
+## Development
+
+For MacOS users, running the tests might throw an error because tests are utilizing [go-mpatch](https://github.com/undefinedlabs/go-mpatch) in order to manipulate the `time.Now` function. The patch allows testing with fixed timestamps.
+
+Instead, MacOS users can utilize the `make test-in-docker` target to execute the tests.