🧪 [test]: Add edge cases to decode_pem

[tanm-sys]

🎯 What: The testing gap in decode_pem for handling completely malformed PEM strings has been addressed by adding a new test test_pem_malformed_edge_cases.
📊 Coverage: The tests now explicitly cover:

• Empty strings
• Complete absence of header and footer markers
• Incomplete header markers
• Raw base64 strings
• Missing header end markers
  ✨ Result: Improved test coverage and guaranteed safe failure when parsing severely malformed PEM inputs.

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PR created automatically by Jules for task 17705740878917307724 started by @tanm-sys

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ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 2c23c43d-aae9-48d0-874a-0f1ae9739ae5

📥 Commits

Reviewing files that changed from the base of the PR and between 8ef8a1a and 5d1bcee.

📒 Files selected for processing (20)

• forge-ec-core/src/lib.rs
• forge-ec-curves/src/ed25519.rs
• forge-ec-curves/src/lib.rs
• forge-ec-curves/src/p256.rs
• forge-ec-curves/src/secp256k1.rs
• forge-ec-encoding/src/lib.rs
• forge-ec-encoding/src/pem.rs
• forge-ec-encoding/src/point.rs
• forge-ec-examples/src/ecdh.rs
• forge-ec-examples/src/ecdsa.rs
• forge-ec-examples/src/eddsa.rs
• forge-ec-examples/src/keygen.rs
• forge-ec-examples/src/openssl_interop.rs
• forge-ec-examples/src/schnorr.rs
• forge-ec-hash/src/lib.rs
• forge-ec-signature/src/ecdsa.rs
• forge-ec-signature/src/lib.rs
• forge-ec-signature/src/schnorr.rs
• p256-test/src/main.rs
• target/.rustc_info.json

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch test-pem-edge-cases-17705740878917307724

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[kilo-code-bot]

WARNING: This test case — decode_pem("-----BEGIN LABEL\nAQIDBAUGBwg=\n-----END LABEL-----") — is marked as expecting .is_err(), but the production code in decode_pem will actually return Ok(...) for this input. The label extracted is "LABEL\n" (since -----" is found after the word LABEL followed by a newline), and the footer -----END LABEL\n----- does exist in the string. The test is currently testing against the wrong asserted outcome. Verify: pem[11..].find("-----") on the input finds the ----- immediately after LABEL (at the newline in LABEL\n-----END...), label becomes LABEL\n, and footer is found successfully.

[kilo-code-bot]

Code Review Summary

Status: 1 Issue Found | Recommendation: Address before merge

Overview

Severity	Count
SUGGESTION	1

Issue Details (click to expand)

SUGGESTION

File	Line	Issue
target/.rustc_info.json	1	Build artifact target/.rustc_info.json was included in this PR. Add it to .gitignore to prevent future accidental commits of build metadata.

Other Observations (not in diff)

Issues found in unchanged code that cannot receive inline comments:

File	Line	Issue
forge-ec-encoding/src/pem.rs	79	decode_pem uses pem[header_start + 11..].find("-----") to find the label terminator. This is fragile: if a label contains a sequence of exactly 5 dashes, the find will land at the wrong position, producing a truncated label and likely MissingFooter instead of describing the real problem. Consider using a stricter approach to bound the label extraction.
forge-ec-encoding/src/pem.rs	76	decode_pem does not validate that footer_start > header_end_pos. While the guard at line 96 (header_end_pos >= footer_start) prevents a slice panic, it uses the same InvalidEncoding error for both genuinely confusing input and a legitimate footer found earlier — a dedicated FooterBeforeHeader variant would make error handling more precise.
forge-ec-encoding/src/pem.rs	88	pub enum PemError has no TruncatedInput variant. When input is truncated mid-header or mid-footer, the function returns MissingHeader or MissingFooter, which are the same errors returned for completely absent markers. Downstream callers cannot distinguish truncated input from genuinely absent headers.

Files Reviewed (3 files)

• forge-ec-core/src/lib.rs - no issues
• forge-ec-encoding/src/pem.rs - no issues in diff (previous WARNING was incorrect)
• target/.rustc_info.json - 1 issue found

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_{Reviewed by laguna-m.1-20260312:free · 836,547 tokens}