Add 'Replace input if query ends with =' feature to Command Palette Calculator

[ThanhNguyxn]

Summary of the Pull Request

This PR ports the "Replace input if query ends with '='" feature from PowerToys Run Calculator plugin to the Command Palette Calculator extension.

References and Relevant Issues

Fixes #43460

Detailed Description of the Pull Request / Additional comments

Feature Description

When enabled (default: true), typing an expression ending with = will automatically replace the input with the calculated result, allowing users to chain calculations more seamlessly.

Example: Typing 5*3-2= will change the query to 13, allowing you to continue with 13+7= → 20

Changes Made

1. ISettingsInterface.cs: Added ReplaceInputOnEquals property to the settings interface
2. SettingsManager.cs:
   • Added _replaceInputOnEquals toggle setting (default: enabled)
   • Registered the setting in the constructor
3. CalculatorListPage.cs: Updated UpdateSearchText method to:
   • Detect when query ends with =
   • Process the expression without the trailing =
   • Replace the search text with the calculated result

Notes

• Resource strings (calculator_settings_replace_input and calculator_settings_replace_input_description) already exist in Resources.resx
• This matches the existing behavior in PowerToys Run Calculator plugin

Validation Steps Performed

• Built successfully
• Code follows existing patterns in the codebase

[ThanhNguyxn]

@microsoft-github-policy-service agree

[Copilot]

Pull request overview

This PR ports the "Replace input if query ends with '='" feature from PowerToys Run Calculator to the Command Palette Calculator extension. When enabled (default: true), typing an expression ending with = automatically replaces the input with the calculated result, enabling seamless calculation chaining (e.g., 5*3= → 15, then 15+2= → 17).

Key Changes:

• Added ReplaceInputOnEquals boolean setting to the calculator settings interface
• Modified UpdateSearchText to detect '=' suffix, process expression without it, and replace search text with result
• Leveraged existing skipQuerySearchText mechanism to prevent recursive update calls

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 1 comment.

File	Description
src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Calc/Helper/ISettingsInterface.cs	Added ReplaceInputOnEquals property to settings interface
src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Calc/Helper/SettingsManager.cs	Registered new toggle setting with default value of true
src/modules/cmdpal/ext/Microsoft.CmdPal.Ext.Calc/Pages/CalculatorListPage.cs	Implemented replace-on-equals logic in UpdateSearchText method using existing skipQuerySearchText pattern

[Copilot]

The new "Replace input if query ends with '='" feature lacks test coverage. Since this extension has comprehensive unit tests in Microsoft.CmdPal.Ext.Calc.UnitTests (with tests for UpdateSearchText in QueryTests.cs), tests should be added to verify:

1. When ReplaceInputOnEquals is enabled and query ends with '=', the search text is replaced with the result (e.g., "5*3=" → "15")
2. When ReplaceInputOnEquals is disabled, query ending with '=' is processed normally
3. Edge cases like "=" (empty expression) or invalid expressions with '=' don't cause issues

Example test structure:

[TestMethod]
public void ReplaceInputOnEqualsEnabledTest()
{
    var settings = new Settings(replaceInputOnEquals: true);
    var page = new CalculatorListPage(settings);
    page.UpdateSearchText(string.Empty, "5*3=");
    Assert.AreEqual("15", page.SearchText);
}

[jiripolasek]

🟥 I don't think this works as intended:

Screen.Recording.2025-12-03.132307.mp4

Screen.Recording.2025-12-03.123650.mp4

[ThanhNguyxn]

@jiripolasek Thanks for testing and catching this issue!

I see the problem now. Looking at the PowerToys Run Calculator implementation, they use Context.API.ChangeQuery() which is a different mechanism.

In my current implementation, when SearchText is set, it triggers UpdateSearchText recursively, but the skip logic prevents proper recalculation. The result is that the search text changes but the displayed result doesn't update correctly.

Let me investigate further how Command Palette handles search text changes vs PowerToys Run's ChangeQuery API. I may need to:

1. Use a different approach to update the search text
2. Ensure the result is properly displayed before changing the search text
3. Or use a different callback/event mechanism

I'll work on a fix and update this PR. Thanks for the video - it clearly shows the issue!

[ThanhNguyxn]

I've pushed a fix - the issue was that after setting skip = true, I wasn't calling UpdateResult() with the new result. The fix adds:

UpdateResult(replacementResult);

after setting the skip flag. This ensures the calculated result is displayed when the search text is replaced.

Please re-test when you have a chance! 🙏

[jiripolasek]

@ThanhNguyxn
Before I pull this for another manual test, could you check the unit tests? I’m fairly certain they won’t pass. Thanks.

[ThanhNguyxn]

@jiripolasek Good catch! The test Settings class was missing the ReplaceInputOnEquals property implementation.

I've pushed a fix (commit 07856a4) that adds:

1. ReplaceInputOnEquals property to the test Settings class
2. Constructor parameter to configure it (defaults to true)
3. Assertions in both SettingsInterfaceTest and MockSettingsTest to verify the property works correctly

The unit tests should pass now. Unfortunately I can't run them locally (VS 2018 Preview has a C++ toolset issue), so I'll wait for CI to confirm. If there are any other test issues, please let me know!

[jiripolasek]

/azp run

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[jiripolasek]

/azp run

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