Fix deserialization error when Homebrew returns null installation timestamps

[Copilot]

Problem

The application was failing to load packages from Homebrew with the following error:

Error loading packages from Homebrew: invalid type: null, expected u64 at line 5159 column 22.
Make sure Homebrew is installed and accessible.

This resulted in only a "homebrew-error" placeholder being displayed instead of the user's installed packages:

Root Cause

The BrewInstalled struct defined the time field as a non-nullable u64, but Homebrew's JSON API can return null for installation timestamps in certain scenarios:

• Packages installed before Homebrew implemented timestamp tracking
• Certain installation methods that don't record timestamps
• Manual installations or package migrations

When serde_json attempted to deserialize a JSON response with a null time field, it raised a deserialization error that prevented all packages from loading.

Solution

Changed the time field from u64 to Option<u64> to handle both valid timestamps and null values gracefully:

pub struct BrewInstalled {
    pub version: String,
    pub time: Option<u64>,  // Now accepts both timestamps and null
    pub installed_as_dependency: bool,
    pub installed_on_request: bool,
}

Packages with null timestamps are treated as having timestamp 0 (Unix epoch) for sorting and comparison purposes, ensuring consistent behaviour across the application.

Changes

• src/entities/brew_info_response.rs: Changed time: u64 → time: Option<u64> and added test for null timestamp deserialization; merged with null homepage handling from main
• src/entities/package_info.rs: Updated to handle Option<u64> when finding the latest installation; includes null homepage handling
• src/repository.rs: Updated timestamp comparison logic to handle optional timestamps; includes null homepage handling
• Cargo.toml: Bumped version from 0.1.3 to 0.1.4
• Cargo.lock: Updated dependencies to latest compatible versions

Testing

• Added new test test_deserialize_formula_with_null_time to verify null timestamps are handled correctly
• Merged with main branch which included tests for null homepage handling
• All 12 tests pass (8 original + 3 for null homepage + 1 for null time)
• No clippy warnings
• Code formatted with rustfmt
• Release build succeeds

Impact

Before: Application crashed when encountering packages with null timestamps
After: All packages load successfully, including those with null timestamps and null homepages

This fix ensures brew-explorer works reliably for all Homebrew installations, regardless of whether packages have timestamp or homepage information available.

Fixes #17

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Fails to load packages — invalid type: null, expected u64 error</issue_title>
<issue_description>After installing brew-explorer via Homebrew, the app opens, spends ~8s loading packages, and then but immediately displays an error instead of listing any packages:

Error loading packages from Homebrew: invalid type: null, expected u64 at line 5159 column 22.  
Make sure Homebrew is installed and accessible.

Observed behavior:

• The UI opens but lists only a placeholder entry named homebrew-error.
• No installed packages are displayed.
• Homebrew commands (brew list, brew info, etc.) function normally outside of brew-explorer.

Environment details:

• System: macOS Sequoia 15.0 (Darwin 25.0.0, arm64 / Apple Silicon)
• Homebrew version: 4.6.17
• Binary location: /opt/homebrew/bin/brew-explorer</issue_description>

Comments on the Issue (you are @copilot in this section)

@cosmincatalin Hi @VildMedPap, I might need some help fixing this.

On my side, I should probably add a better error message.

On your side, can you do some debugging similar to what was done in #2 by @unnamedd?</comment_new>
<comment_new>@cosmincatalin
Brilliant, I'll fix it asap.</comment_new>

Fixes #17

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[cosmincatalin]

You need to also bump the version

[cosmincatalin]

The version of the package needs to be bumped up at patch version.
cargo udpate needs to be run.
@copilot

[cosmincatalin]

The version of the app needs to be bumped with a patch increment.
After this, cargo update needs to be run.

[cosmincatalin]

@copilot , fix the conflicts and do the work.

[Copilot]

@copilot , fix the conflicts and do the work.

Fixed merge conflicts and bumped version to 0.1.4 in commit 70f32cb. The branch now includes both the null time field fix and the null homepage fix from main. All 12 tests pass.

@copilot , fix the conflicts and do the work.

Fixed merge conflicts and bumped version to 0.1.4 in commit 1f94ca8. The branch now includes both the null time field fix and the null homepage fix from main. All 12 tests pass.