Fix/afterheader tail truncation#144
Merged
2 commits merged intoJul 18, 2026
Merged
Conversation
insert.AfterHeader returned content[:insertPoint] + entry, truncating the file at the insertion point and silently discarding the tail. Its sole caller is beforeFirstEntry's fallback, taken when a knowledge file has no `## [` entry — so `ctx learning add` / `ctx decision add` against an entry-less LEARNINGS.md/DECISIONS.md destroyed any content below the H1 header and its comment block. Same family as the clobber bug index.Validate guards: silent loss of persisted memory, git-only recovery. Masked today because an entry-less file from `ctx init` has nothing after the comment block (empty tail), so nothing was lost yet — but any hand-written section below the preamble of an as-yet-entry-less file was one add away from deletion. Fix: preserve the tail (the pattern sibling Task already uses). Empty tail returns the original bytes unchanged, so every file shape that works today is byte-identical; only the losing shape changes. When a tail follows, the entry is separated from it by a `---` rule. The package had no tests. Added insert_test.go (tail-preserved, empty-tail-unchanged, primary-path-unchanged) and a TestMain calling lookup.Init() — without it desc.Text returns "" and strings.Index(s,"") == 0 silently rewrites every insert anchor to offset 0, so tests would pass exercising a path production never takes. Verified end-to-end against the built binary: a Notes section below the preamble survives `ctx learning add` and the entry lands above it. Found by the layout proof for specs/progressive-disclosure.md; the fix stands alone and ships alone. Spec: specs/fix-afterheader-tail-truncation.md Signed-off-by: Jose Alekhinne <jose@ctx.ist>
Two gotchas from fixing the AfterHeader truncation: - desc.Text() returns "" in a test binary without lookup.Init(), and strings.Index(s, "") == 0 turns anchor-based inserts into offset-0 matches — tests pass exercising a path production never takes. - An insert helper returning content[:i]+x without content[i:] is append-with-truncation, not insert; a lone content[:i] is the smell. Spec: specs/fix-afterheader-tail-truncation.md Signed-off-by: Jose Alekhinne <jose@ctx.ist>
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
No description provided.