[georgianastasov]

Closes: #1873

Description

Fix Windows-specific drive-letter casing issues where glob returns paths starting with an uppercase drive letter (C:/), while the CLI source path may use lowercase (c:/).

Case-sensitive path handling could cause:

• False "already exists" errors during template validation.
• Overwriting and emptying original template files during project generation.
• AI skills failing to copy into generated projects.
• Project generation reporting success even when template processing failed.

Changes:

• Use glob with cwd and path.join() instead of string-based path replacement.
• Prevent accidental source template overwrites.
• Stop ig new and the interactive wizard when template processing fails, avoiding false success messages.
• Remove obsolete React and Web Components template path overrides referencing missing directories.
• Fix AI skills copying on Windows by using native path.relative() to handle drive-letter casing correctly.
• Extend regression coverage for Windows path casing, special characters, template collisions, generation failures, AI skills copying, and template directory validation.

Related Issue

N/A

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update
• Refactoring / code cleanup
• Build / CI configuration change

Affected Packages

• igniteui-cli (packages/cli)
• @igniteui/cli-core (packages/core)
• @igniteui/angular-templates (packages/igx-templates)
• @igniteui/angular-schematics (packages/ng-schematics)
• @igniteui/mcp-server (packages/igniteui-mcp)

Checklist

• I have tested my changes locally (npm run test)
• I have built the project successfully (npm run build)
• I have run the linter (npm run lint)
• I have added/updated tests as needed
• My changes do not introduce new warnings or errors

Additional Context

Verification:

• 23/23 FIXED CLI manual E2E tests passed across the original Windows regression scenarios.
• Previously verified: 31 unit tests and 21 template collision tests passed.
• Manual CLI tests passed for ig new (Angular, jQuery, React, Web Components), ig add, and ig generate.
• Verified AI skills copying with lowercase Windows drive-letter paths.
• Confirmed generated files are correct and original template sources remain unchanged.

[coveralls]

coverage: 95.379%. remained the same — ganastasov/windows-template-path-corruption into master

[Copilot]

🟡 Changes recommended

Critical gaps in the path guard allow symlink/junction aliases and transformed filenames to truncate or overwrite source templates when validation is disabled.

2 open issues

• Reject symlinked destination paths that alias the source directory · New
• Prevent transformed outputs from overwriting source templates · New

What changed in this PR

This PR addresses #1873 by replacing case-sensitive path substitution in core template processing, preventing Windows drive-letter casing differences from misdirecting generated files.

Changes:

• Discover templates relative to their source directory and construct paths with path.join().
• Add a guard against overwriting the current source template.
• Add regression tests for special-character paths, collisions, and Windows drive-letter casing.

File	Description
spec/​unit/​Util-spec.ts	Adds filesystem-based regression tests for template generation and source preservation.
packages/​core/​util/​Util.ts	Updates path construction in processing and validation, and adds a source-overwrite guard.

_{Review effort: Balanced}

[Copilot]

🟢 Approval recommended

No active review issues block the template-processing and generation-failure handling changes.

No open issues 🎉

2 resolved since last review

• Prevent transformed outputs from overwriting source templates
• Reject symlinked destination paths that alias the source directory

_{Review effort: Balanced}

[Marina-L-Stoyanova]

While testing this PR I notices that AI skills are not copied on Windows when the CLI path uses a lowercase drive letter. I think we can fix this as part of the current PR.

[georgianastasov]

Thanks. I reproduced the issue on Windows and confirmed that it also exists in the published CLI 15.8.2, so it's not a regression introduced by this PR. I also reproduced it with the current PR changes:

• Uppercase C:\ - all 18 AI skill files copied successfully.
• Lowercase c:\ - all 18 files failed to copy.

Since it's caused by the same Windows drive-letter casing issue, I'll include the fix and a regression test in this PR as well.