Added CRAN release checklist.

Author: jwood000

.Rbuildignore

@@ -11,3 +11,4 @@ create_md.R
 SO_Answers/*
 ^codecov\.yml$
 ^_pkgdown\.yml$
+^CRAN_RELEASE_CHECKLIST.md$

CRAN_RELEASE_CHECKLIST.md

@@ -0,0 +1,236 @@
+# CRAN Release Checklist (RcppAlgos)
+
+This checklist is optimized for small patch releases and CRAN pretests
+(CITATION readability, URL validity, clean tarball contents).
+
+---
+
+## 0) Before you start
+
+- [ ] Confirm you are on a clean release branch (no WIP for the next large release).
+- [ ] `git status` is clean (or only includes intentional release edits).
+- [ ] Review staged changes (ignore pkgdown output as needed):
+  - [ ] `git diff --stat`
+  - [ ] `git diff <prev_tag>..HEAD -- . ':(exclude)docs'`
+
+---
+
+## 1) Versioning + changelog
+
+- [ ] Bump version in `DESCRIPTION` (e.g., `2.9.4` → `2.9.5`).
+- [ ] Update `NEWS.md` with a new top entry.
+- [ ] Update `man/NEWS.Rd` (if shipped) to match `NEWS.md`.
+
+---
+
+## 2) CITATION (CRAN incoming pretest requirement)
+
+- [ ] Update `inst/CITATION`.
+- [ ] Ensure `inst/CITATION` contains **no dynamic calls** that require the package
+      to be installed/available (e.g., no `packageVersion()`, `Sys.Date()`,
+      `utils::packageDescription()`, `citation()`, etc.).
+- [ ] Ensure URLs are canonical (e.g., trailing slashes where applicable).
+- [ ] Local verification:
+  - [ ] `R -q -e "tools::checkRdaFiles('.')"` (optional)
+  - [ ] Build + check tarball (see section 5) and confirm no:
+    - “Reading CITATION file fails … when package is not installed.”
+
+---
+
+## 3) URLs + metadata
+
+- [ ] Run URL checks (fix true errors):
+  - [ ] `R -q -e "urlchecker::url_check()"`
+- [ ] Fix:
+  - [ ] Invalid fragments (bad `#...` URLs)
+  - [ ] True 404s
+  - [ ] Permanent redirects (301) by switching to canonical URL (often add trailing slash)
+- [ ] Confirm `DESCRIPTION` includes canonical URLs (pkgdown + GitHub), e.g.:
+  - [ ] `URL: https://jwood000.github.io/RcppAlgos/, https://github.com/jwood000/RcppAlgos`
+  - [ ] `BugReports: https://github.com/jwood000/RcppAlgos/issues`
+
+---
+
+## 4) Build hygiene (.Rbuildignore)
+
+- [ ] Ensure non-package files are excluded in `.Rbuildignore`, at minimum:
+  - [ ] `^docs$` (pkgdown output)
+  - [ ] `^_pkgdown\.yml$`
+  - [ ] `^CRAN_RELEASE_CHECKLIST\.md$`
+  - [ ] Any local tooling directories (e.g., `^ai_git_helpers$`)
+- [ ] Confirm `R CMD build` tarball does not include website/config extras.
+
+---
+
+## 5) Local checks (must be clean)
+
+Run checks from a clean state.
+
+- [ ] `R CMD build .`
+- [ ] `R CMD check RcppAlgos_<version>.tar.gz --as-cran`
+
+Verify:
+- [ ] No ERRORs or WARNINGs.
+- [ ] Any NOTEs are understood/acceptable (avoid new NOTES if possible).
+- [ ] In particular:
+  - [ ] CITATION readable in incoming feasibility checks
+  - [ ] No invalid URLs (especially malformed GitHub links)
+  - [ ] No new “non-standard file/directory found at top level”
+
+---
+
+## 6) pkgdown site (optional for CRAN, recommended for releases)
+
+If maintaining the site for each release:
+
+- [ ] Update `_pkgdown.yml` as needed (bootstrap, url).
+- [ ] `R -q -e "pkgdown::build_site()"`
+- [ ] Commit site output under `docs/` (if that is the repo policy).
+- [ ] If pkgdown warns about missing alt text, consider fixing in README/vignettes.
+
+---
+
+## 7) External builders
+
+- [ ] Win-builder:
+  - [ ] devel
+  - [ ] release
+  - [ ] oldrelease
+- [ ] (Recommended) CI matrix / GitHub Actions:
+  - [ ] at least Linux + macOS
+  - [ ] include r-devel somewhere if practical
+
+---
+
+## 8) Final review + tagging
+
+- [ ] Review final diff (excluding docs):
+  - [ ] `git diff <prev_tag>..HEAD -- . ':(exclude)docs'`
+- [ ] Confirm `DESCRIPTION` fields (at least):
+  - [ ] `Version`
+  - [ ] `URL` (canonical)
+  - [ ] `BugReports`
+- [ ] Create release tag:
+  - [ ] `git tag -a v<version> -m "CRAN patch release <version>"`
+  - [ ] `git push --tags`
+
+---
+
+## 9) CRAN submission
+
+- [ ] Prepare `cran-comments.md` (if used), include:
+  - [ ] Summary of changes
+  - [ ] Any NOTE explanations (if any remain)
+  - [ ] Mention that CITATION/URL issues from incoming pretests were corrected
+- [ ] Submit via `devtools::submit_cran()` or CRAN web form.
+
+---
+
+## Quick commands (copy/paste)
+
+### Diff ignoring pkgdown output
+
+```sh
+git diff <old> <new> -- . ':(exclude)docs'
+```
+
+### Build + check
+
+```sh
+R CMD build .
+R CMD check RcppAlgos_*.tar.gz --as-cran
+```
+
+### URL check
+
+```r
+urlchecker::url_check()
+```
+
+### pkgdown
+
+```r
+pkgdown::build_site()
+```
+
+## Docker UBSan (r-devel-ubsan-clang) sanity check (recommended for C++ changes)
+
+This is a quick way to catch undefined behavior (UB) that may not show up in
+regular checks. Uses the rocker image: `rocker/r-devel-ubsan-clang`.
+
+### 1) Start Docker
+- [ ] Open Docker Desktop and ensure it is running.
+
+### 2) Run the container (mount repo)
+> `--rm` removes the container when you exit; the repo is mounted in.
+
+```sh
+docker run --platform linux/amd64 -m=10g --cap-add SYS_PTRACE \
+  --name=r-devel-ubsan-clang \
+  -v ~/RcppAlgos:/RSource/RcppAlgos \
+  --rm -ti rocker/r-devel-ubsan-clang /bin/bash
+```
+
+### 3) Install system deps (inside container)
+
+```sh
+apt-get update
+apt-get install -y libgmp3-dev
+```
+
+### 4) Install R deps (inside container)
+
+```sh
+R -e 'install.packages(c("cpp11","gmp","testthat","microbenchmark","numbers","partitions"), repos="https://cloud.r-project.org")'
+R -e 'install.packages("RcppBigIntAlgos", repos="https://cloud.r-project.org")'
+```
+
+### 5) Build + check package (inside container)
+
+```sh
+R CMD build /RSource/RcppAlgos
+Rdevel CMD check --no-examples --no-vignettes RcppAlgos_*.tar.gz
+```
+
+Notes:
+
+* Use `--no-examples --no-vignettes` for speed. Remove these flags when debugging
+  vignette/example-related issues.
+* If you are investigating memory/UB issues deeply, consider running without
+  `--no-vignettes` to widen coverage.
+
+---
+
+## Debugging UBSan traces (addr2line)
+
+Sometimes UBSan prints stack frames with offsets into the shared object, e.g.:
+
+`/RcppAlgos.Rcheck/RcppAlgos/libs/RcppAlgos.so+0x3034db`
+
+You can map these offsets back to source lines using `addr2line`.
+
+### 1) Locate the compiled shared object and the offset
+
+Example:
+
+* SO: `/RcppAlgos.Rcheck/RcppAlgos/libs/RcppAlgos.so`
+* Offset: `0x3034db`
+
+### 2) Convert offset to file:line
+
+```sh
+addr2line -e /RcppAlgos.Rcheck/RcppAlgos/libs/RcppAlgos.so -f -C 0x3034db
+```
+
+Recommended:
+
+* `-f` prints function name
+* `-C` demangles C++ symbols
+
+### 3) If symbolization is missing / warnings appear
+
+If you see messages like:
+`WARNING: Failed to use and restart external symbolizer!`
+
+Try installing/ensuring LLVM symbolizer tools are present, then re-run.
+(Exact package names can vary across base images.)