fix: format MountType with %v in bind mount diagnostic

[vulragrag-star]

What does this PR do?

In mapToDockerMounts, the BindMounter diagnostic used %s with MountType (a uint with no String method). That produces a fmt error marker such as %!s(testcontainers.MountType=0) instead of the type value. This changes the verb to %v and adds a unit test for the diagnostic format.

Why is it important?

Unsupported-bind-mount errors should show a readable mount type so the diagnostic is usable when debugging mount configuration.

Related issues

• Closes [Bug]: Unsupported mount diagnostic formats MountType with a string verb #3909

How to test this PR

go test -run TestMapToDockerMountsBindDiagnosticFormat .

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📥 Commits

Reviewing files that changed from the base of the PR and between 096293a and 57909de.

📒 Files selected for processing (2)

• docker_mounts.go
• docker_mounts_test.go

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Summary by CodeRabbit

• Bug Fixes
  • Corrected unsupported mount-type diagnostics so they display the mount type without a formatting error marker.

Walkthrough

The unsupported mount diagnostic now formats the mount type with %v instead of %s. A test captures the log output and checks that it contains no formatting error marker.

Changes

Mount Diagnostic Formatting

Layer / File(s)	Summary
Diagnostic formatting and test docker_mounts.go, docker_mounts_test.go	The diagnostic uses %v to format the mount type. The test captures the log output and checks that it has no formatting error marker. It restores the previous default logger during cleanup.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~5 minutes

Change: Bug fix · Severity of issue fixed: Low

Suggested reviewers: mdelapenya

Merge Risk: ⚪ Minimal · up to 57909

The diagnostic formatting issue is addressed and covered by a focused test; no material merge risk remains.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Docstring Coverage	⚠️ Warning	Docstring coverage is 50.00% which is insufficient. The required threshold is 80.00%. Docstring coverage is scoped to functions touched by this diff. Analyzed 2 functions across 2 files.	Write docstrings for the functions missing them to satisfy the coverage threshold.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly and concisely describes the main change: formatting MountType with %v in the bind-mount diagnostic.
Description check	✅ Passed	The description directly explains the formatting defect, the code change, the added test, and the debugging benefit.
Linked Issues check	✅ Passed	The PR meets the coding requirement in issue #3909. mapToDockerMounts changes the MountType diagnostic verb from %s to %v, which removes the fmt error marker and preserves the mount type val…
Out of Scope Changes check	✅ Passed	The reported changes stay within issue #3909. They modify only the affected diagnostic format and add focused test coverage for that format. No unrelated mount behavior or public API change is reporte…

• Fix all pre-merge checks with AI

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create a new PR

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_{A rabbit checks the mount log line,
The type now prints without a sign
Of formatting trouble in the stream,
A test confirms the output’s clean,
Then hops away to nibble greens.}

_{Comment @coderabbitai help to get the list of available commands.}