abstract clone repo to test better

Author: jalafel

cmd/gh-classroom/clone/utils/clone-repository.go

@@ -0,0 +1,32 @@
+// cmd/gh-classroom/clone/utils/clone-repository.go
+
+package utils
+
+import (
+    "fmt"
+    "os"
+    "bytes"
+)
+
+// GitHubExec defines an interface for executing GitHub CLI commands.
+// This abstraction allows for easier testing and decoupling from the actual CLI.
+// Exec invokes a gh command in a subprocess and captures the output and error streams.
+type GitHubExec interface {
+    Exec(args ...string) (stdout, stderr bytes.Buffer, err error)
+}
+
+// CloneRepository attempts to clone a repository into the specified path.
+// It returns an error if the cloning process fails.
+func CloneRepository(clonePath string, repoFullName string, gh GitHubExec) error {
+    if _, err := os.Stat(clonePath); os.IsNotExist(err) {
+        fmt.Printf("Cloning into: %v\n", clonePath)
+        _, _, err := gh.Exec("repo", "clone", repoFullName, "--", clonePath)
+        if err != nil {
+            fmt.Printf("error cloning %s: %v\n", repoFullName, err)
+            return fmt.Errorf("error cloning %s: %v", repoFullName, err)
+        }
+        return nil // Success
+    }
+    fmt.Printf("Skip existing repo: %v use gh classroom pull to get new commits\n", clonePath)
+    return fmt.Errorf("repository already exists: %s", clonePath)
+}

cmd/gh-classroom/clone/utils/clone-repository_test.go

@@ -0,0 +1,100 @@
+package utils
+
+import (
+    "io/ioutil"
+    "os"
+    "testing"
+    "bytes"
+    "fmt"
+    "errors"
+    "path/filepath"
+)
+
+// MockGitHubExec is a mock of the GitHubExec interface for testing.
+type MockGitHubExec struct {
+    ExecFunc func(args ...string) (stdout, stderr bytes.Buffer, err error)
+}
+
+func (m *MockGitHubExec) Exec(args ...string) (stdout, stderr bytes.Buffer, err error) {
+    return m.ExecFunc(args...)
+}
+
+
+func TestCloneRepository(t *testing.T) {
+    tmpDir, err := ioutil.TempDir("", "cloneTest")
+    if err != nil {
+        t.Fatalf("Failed to create temp directory: %v", err)
+    }
+    defer os.RemoveAll(tmpDir) // clean up
+    // Test cases
+    tests := []struct {
+        name       string
+        execMock   *MockGitHubExec
+        clonePath  string
+        repoFullName string
+        wantErr    bool
+        errMsg     string
+    }{
+        {
+            name: "successful clone",
+            execMock: &MockGitHubExec{
+                ExecFunc: func(args ...string) (stdout bytes.Buffer, stderr bytes.Buffer, err error) {
+                    var stdoutBuf, stderrBuf bytes.Buffer
+                    stdoutBuf.Write([]byte("your string here"))
+                    return stdoutBuf, stderrBuf, nil
+                },
+            },
+            clonePath: "", // Will be set to a temp directory in the test
+            repoFullName: "example/repo",
+            wantErr:    false,
+        },
+        {
+            name: "clone failure",
+            execMock: &MockGitHubExec{
+                ExecFunc: func(args ...string) (stdout bytes.Buffer, stderr bytes.Buffer, err error) {
+                    var stdoutBuf, stderrBuf bytes.Buffer
+                    return stdoutBuf, stderrBuf, errors.New("clone error")
+                },
+            },
+            clonePath:  filepath.Join(tmpDir, "repo"),
+            repoFullName: "example/repo",
+            wantErr:    true,
+            errMsg:     "error cloning example/repo: clone error",
+        },
+        {
+            name: "repository already exists",
+            execMock: &MockGitHubExec{
+                ExecFunc: func(args ...string) (stdout bytes.Buffer, stderr bytes.Buffer, err error) {
+                    var stdoutBuf, stderrBuf bytes.Buffer
+                    return stdoutBuf, stderrBuf, nil
+                },
+            },
+            clonePath:  "./repo", // Current directory always exists
+            repoFullName: "example/repo",
+            wantErr:    true,
+            errMsg:     "repository already exists: .",
+        },
+    }
+
+
+    for _, tt := range tests {
+        t.Run(tt.name, func(t *testing.T) {
+            if tt.name == "successful clone" {
+                fmt.Println("Running successful clone test")
+                tmpDir, err := ioutil.TempDir("", "cloneTest")
+                if err != nil {
+                    t.Fatalf("Failed to create temp directory: %v", err)
+                }
+                defer os.RemoveAll(tmpDir) // clean up
+                tt.clonePath = filepath.Join(tmpDir, "repo")
+            }
+
+
+            fmt.Println("Running test", tt.name, "with clonePath", tt.clonePath, "and repoFullName", tt.repoFullName)
+            err := CloneRepository(tt.clonePath, tt.repoFullName, tt.execMock)
+            if err != nil && err.Error() != tt.errMsg {
+                t.Errorf("CloneRepository() error = %v, wantErr %v", err, tt.wantErr)
+            }
+        })
+    }
+}