opentofu/configs/configload/testing.go
Martin Atkins 591aaf1e6a configload: helper functions for tests
These utility functions are intended to allow concisely loading a
configuration from a fixture directory in a test, bailing out early if
there are any unexpected errors.
2018-10-16 18:24:47 -07:00

102 lines
3.2 KiB
Go

package configload
import (
"io/ioutil"
"os"
"testing"
"github.com/hashicorp/terraform/configs"
"github.com/hashicorp/terraform/tfdiags"
)
// NewLoaderForTests is a variant of NewLoader that is intended to be more
// convenient for unit tests.
//
// The loader's modules directory is a separate temporary directory created
// for each call. Along with the created loader, this function returns a
// cleanup function that should be called before the test completes in order
// to remove that temporary directory.
//
// In the case of any errors, t.Fatal (or similar) will be called to halt
// execution of the test, so the calling test does not need to handle errors
// itself.
func NewLoaderForTests(t *testing.T) (*Loader, func()) {
t.Helper()
modulesDir, err := ioutil.TempDir("", "tf-configs")
if err != nil {
t.Fatalf("failed to create temporary modules dir: %s", err)
return nil, func() {}
}
cleanup := func() {
os.RemoveAll(modulesDir)
}
loader, err := NewLoader(&Config{
ModulesDir: modulesDir,
})
if err != nil {
cleanup()
t.Fatalf("failed to create config loader: %s", err)
return nil, func() {}
}
return loader, cleanup
}
// LoadConfigForTests is a convenience wrapper around NewLoaderForTests,
// Loader.InstallModules and Loader.LoadConfig that allows a test configuration
// to be loaded in a single step.
//
// If module installation fails, t.Fatal (or similar) is called to halt
// execution of the test, under the assumption that installation failures are
// not expected. If installation failures _are_ expected then use
// NewLoaderForTests and work with the loader object directly. If module
// installation succeeds but generates warnings, these warnings are discarded.
//
// If installation succeeds but errors are detected during loading then a
// possibly-incomplete config is returned along with error diagnostics. The
// test run is not aborted in this case, so that the caller can make assertions
// against the returned diagnostics.
//
// As with NewLoaderForTests, a cleanup function is returned which must be
// called before the test completes in order to remove the temporary
// modules directory.
func LoadConfigForTests(t *testing.T, rootDir string) (*configs.Config, *Loader, func(), tfdiags.Diagnostics) {
t.Helper()
var diags tfdiags.Diagnostics
loader, cleanup := NewLoaderForTests(t)
hclDiags := loader.InstallModules(rootDir, true, InstallHooksImpl{})
if diags.HasErrors() {
cleanup()
diags = diags.Append(hclDiags)
t.Fatal(diags.Err())
return nil, nil, cleanup, diags
}
config, hclDiags := loader.LoadConfig(rootDir)
diags = diags.Append(hclDiags)
return config, loader, cleanup, diags
}
// MustLoadConfigForTests is a variant of LoadConfigForTests which calls
// t.Fatal (or similar) if there are any errors during loading, and thus
// does not return diagnostics at all.
//
// This is useful for concisely writing tests that don't expect errors at
// all. For tests that expect errors and need to assert against them, use
// LoadConfigForTests instead.
func MustLoadConfigForTests(t *testing.T, rootDir string) (*configs.Config, *Loader, func()) {
t.Helper()
config, loader, cleanup, diags := LoadConfigForTests(t, rootDir)
if diags.HasErrors() {
cleanup()
t.Fatal(diags.Err())
}
return config, loader, cleanup
}