refactor to ensure code doesn't depend on integration code

pkg/integration/cmd/injector/main.go

@@ -0,0 +1,47 @@
+package main
+
+import (
+	"os"
+
+	"github.com/jesseduffield/lazygit/pkg/app"
+	"github.com/jesseduffield/lazygit/pkg/integration"
+	integrationTypes "github.com/jesseduffield/lazygit/pkg/integration/types"
+)
+
+// The purpose of this program is to run lazygit with an integration test passed in.
+// We could have done the check on LAZYGIT_TEST_NAME in the root main.go but
+// that would mean lazygit would be depending on integration test code which
+// would bloat the binary.
+
+// You should not invoke this program directly. Instead you should go through
+// pkg/integration/cmd/runner/main.go or pkg/integration/cmd/tui/main.go
+
+func main() {
+	dummyBuildInfo := &app.BuildInfo{
+		Commit:      "",
+		Date:        "",
+		Version:     "",
+		BuildSource: "integration test",
+	}
+
+	integrationTest := getIntegrationTest()
+
+	app.Start(dummyBuildInfo, integrationTest)
+}
+
+func getIntegrationTest() integrationTypes.IntegrationTest {
+	integrationTestName := os.Getenv("LAZYGIT_TEST_NAME")
+	if integrationTestName == "" {
+		panic("expected LAZYGIT_TEST_NAME environment variable to be set, given that we're running an integration test")
+	}
+
+	// unsetting so that if we run lazygit in as a 'daemon' we don't think we're trying to run a test again
+	os.Unsetenv("LAZYGIT_TEST_NAME")
+	for _, candidateTest := range integration.Tests {
+		if candidateTest.Name() == integrationTestName {
+			return candidateTest
+		}
+	}
+
+	panic("Could not find integration test with name: " + integrationTestName)
+}