mend/fs_test.go

/*
another test that is entirely ae ayee generated
- ruinivist, 30Dec25
*/

package main

import (
	"os"
	"path/filepath"
	"testing"
)

func TestWalkFileSystemAndBuildTree(t *testing.T) {
	t.Run("build tree from real directory", func(t *testing.T) {
		// Create temporary directory structure
		tmpDir := t.TempDir()

		// Create test structure:
		// tmpDir/
		//   file1.txt
		//   file2.go
		//   folder1/
		//     nested.txt
		//   folder2/
		os.WriteFile(filepath.Join(tmpDir, "file1.txt"), []byte("content"), 0644)
		os.WriteFile(filepath.Join(tmpDir, "file2.go"), []byte("code"), 0644)
		os.Mkdir(filepath.Join(tmpDir, "folder1"), 0755)
		os.WriteFile(filepath.Join(tmpDir, "folder1", "nested.txt"), []byte("nested"), 0644)
		os.Mkdir(filepath.Join(tmpDir, "folder2"), 0755)

		// Build tree
		root := &FsNode{
			nodeType: FolderNode,
			path:     tmpDir,
			children: make([]*FsNode, 0),
			expanded: true,
		}

		err := walkFileSystemAndBuildTree(tmpDir, root)
		if err != nil {
			t.Fatalf("walkFileSystemAndBuildTree() error = %v", err)
		}

		// Verify structure
		if len(root.children) != 4 {
			t.Fatalf("root children count = %d, want 4", len(root.children))
		}

		// Check children exist and have correct types
		fileCount := 0
		folderCount := 0
		var folder1 *FsNode

		for _, child := range root.children {
			if child.parent != root {
				t.Errorf("child %q parent pointer incorrect", child.FileName())
			}

			if child.nodeType == FileNode {
				fileCount++
			} else if child.nodeType == FolderNode {
				folderCount++
				if child.FileName() == "folder1" {
					folder1 = child
				}
			}
		}

		if fileCount != 2 {
			t.Errorf("file count = %d, want 2", fileCount)
		}
		if folderCount != 2 {
			t.Errorf("folder count = %d, want 2", folderCount)
		}

		// Verify nested structure
		if folder1 == nil {
			t.Fatal("folder1 not found")
		}
		if len(folder1.children) != 1 {
			t.Errorf("folder1 children count = %d, want 1", len(folder1.children))
		}
		if folder1.children[0].FileName() != "nested.txt" {
			t.Errorf("nested file name = %q, want %q", folder1.children[0].FileName(), "nested.txt")
		}
		if folder1.children[0].nodeType != FileNode {
			t.Errorf("nested node type = %v, want %v", folder1.children[0].nodeType, FileNode)
		}
	})

	t.Run("error when node is nil", func(t *testing.T) {
		tmpDir := t.TempDir()
		err := walkFileSystemAndBuildTree(tmpDir, nil)
		if err == nil {
			t.Fatal("walkFileSystemAndBuildTree() with nil node should return error")
		}
		if err.Error() != "node cannot be nil" {
			t.Errorf("error message = %q", err.Error())
		}
	})

	t.Run("error when node already has children", func(t *testing.T) {
		tmpDir := t.TempDir()
		root := &FsNode{
			nodeType: FolderNode,
			path:     tmpDir,
			children: []*FsNode{{nodeType: FileNode, path: "dummy"}},
			expanded: true,
		}

		err := walkFileSystemAndBuildTree(tmpDir, root)
		if err == nil {
			t.Fatal("walkFileSystemAndBuildTree() with existing children should return error")
		}
		if err.Error() != "node already has children" {
			t.Errorf("error message = %q", err.Error())
		}
	})

	t.Run("error when path does not exist", func(t *testing.T) {
		root := &FsNode{
			nodeType: FolderNode,
			path:     "/nonexistent/path",
			children: make([]*FsNode, 0),
			expanded: true,
		}

		err := walkFileSystemAndBuildTree("/nonexistent/path", root)
		if err == nil {
			t.Fatal("walkFileSystemAndBuildTree() with nonexistent path should return error")
		}
	})

	t.Run("empty directory", func(t *testing.T) {
		tmpDir := t.TempDir()
		root := &FsNode{
			nodeType: FolderNode,
			path:     tmpDir,
			children: make([]*FsNode, 0),
			expanded: true,
		}

		err := walkFileSystemAndBuildTree(tmpDir, root)
		if err != nil {
			t.Fatalf("walkFileSystemAndBuildTree() error = %v", err)
		}

		if len(root.children) != 0 {
			t.Errorf("empty directory should have 0 children, got %d", len(root.children))
		}
	})
}