1 files changed, 110 insertions, 0 deletions
diff --git a/main_test.go b/main_test.go
new file mode 100644
index 0000000..438ce7f
--- /dev/null
+++ b/main_test.go
@@ -0,0 +1,110 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/alecthomas/assert/v2"
+)
+
+var prefix = "/nix/store/x2kkw05xdx9g0aqvgl5lnnypq9fvv2sn-"
+
+func TestParseStorePathWithoutOutput(t *testing.T) {
+	path := prefix + "some-name-01.23.45"
+	out, err := parseStorePath(outputNameRe, path)
+	assert.NoError(t, err)
+	assert.Equal(t, out, &Dependency{
+		Name:    "some-name",
+		Version: "01.23.45",
+		Output:  "",
+		Path:    path,
+	})
+}
+
+func TestParseStorePathWithOutput(t *testing.T) {
+	path := prefix + "some-name-01.23.45-some123output"
+	out, err := parseStorePath(outputNameRe, path)
+	assert.NoError(t, err)
+	assert.Equal(t, out, &Dependency{
+		Name:    "some-name",
+		Version: "01.23.45",
+		Output:  "some123output",
+		Path:    path,
+	})
+}
+
+func TestParseStorePathNoName(t *testing.T) {
+	path := "/nix/store/l7rjijvn6vx8njaf95vviw5krn3i9nnx"
+	_, err := parseStorePath(nil, path)
+	assert.Equal(t, err, fmt.Errorf("path %s did not start with digest", path))
+}
+
+func versionChange(name string, output string, oldVersions, newVersions []string) VersionChange {
+	return VersionChange{
+		Name:   name,
+		Output: output,
+		OldVersions: mapSlice(oldVersions, func(v string) Version {
+			return Version{v, []string{fmt.Sprintf("%s-%s-%s", name, v, output)}}
+		}),
+		NewVersions: mapSlice(newVersions, func(v string) Version {
+			return Version{v, []string{fmt.Sprintf("%s-%s-%s", name, v, output)}}
+		}),
+	}
+}
+
+func TestPrintChanges(t *testing.T) {
+	added := []Dependency{
+		{
+			Name:    "new-foo",
+			Version: "1.2.3",
+			Output:  "",
+			Path:    "/nix/store/digest-new-foo-1.2.3",
+		},
+		{
+			Name:    "new-bar",
+			Version: "1.2.3",
+			Output:  "some-output",
+			Path:    "/nix/store/digest-new-bar-1.2.3",
+		},
+	}
+	removed := []Dependency{
+		{
+			Name:    "removed-foo",
+			Version: "1.2.3",
+			Output:  "",
+			Path:    "/nix/store/digest-removed-foo-1.2.3",
+		},
+		{
+			Name:    "removed-bar",
+			Version: "1.2.3",
+			Output:  "some-output",
+			Path:    "/nix/store/digest-removed-bar-1.2.3",
+		},
+	}
+	changed := []VersionChange{
+		versionChange("changed-foo", "", []string{"1.2.3"}, []string{"1.2.4"}),
+		versionChange("changed-foo", "man", []string{"1.2.3"}, []string{"1.2.4"}), // will be omitted
+		versionChange("changed-foo", "bar", []string{"1.2.3"}, []string{"1.2.5"}),
+		versionChange("changed-bar", "some-output", []string{"1.2.3"}, []string{"1.2.4"}),
+	}
+
+	var sb strings.Builder
+	printChanges(&sb, added, removed, changed, map[string]bool{"changed-bar-1.2.4-some-output": true})
+
+	assert.Equal(t, sb.String(), strings.TrimLeft(`
+Version changed:
+  changed-bar(some-output): 1.2.3 -> 1.2.4
+
+  changed-foo: 1.2.3 -> 1.2.4
+  changed-foo(bar): 1.2.3 -> 1.2.5
+
+Added packages:
+  new-bar(some-output) 1.2.3
+  new-foo 1.2.3
+
+Removed packages:
+  removed-bar(some-output) 1.2.3
+  removed-foo 1.2.3
+`, "\n"))
+}