From 78677770f84783bea528df410ebc13ec506240b0 Mon Sep 17 00:00:00 2001
From: stubbsta <tanya.steyn22@gmail.com>
Date: Thu, 21 May 2026 12:25:12 +0200
Subject: [PATCH] improve install_nim script

---
 scripts/install_nim.sh | 42 +++++++++++++++++++++++-------------------
 1 file changed, 23 insertions(+), 19 deletions(-)

diff --git a/scripts/install_nim.sh b/scripts/install_nim.sh
index c8d0f439d..ce71c0345 100755
--- a/scripts/install_nim.sh
+++ b/scripts/install_nim.sh
@@ -17,26 +17,28 @@ if [ -z "${NIM_VERSION}" ]; then
   exit 1
 fi
 
-# Check if the right version is already installed
-nim_ver=$(nim --version 2>/dev/null | head -1 | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' | head -1 || true)
-if [ "${nim_ver}" = "${NIM_VERSION}" ]; then
-  echo "Nim ${NIM_VERSION} already installed, skipping."
+NIM_DEST="${HOME}/.nim/nim-${NIM_VERSION}"
+
+# Check if nim is already installed at our expected location (not just anywhere in PATH).
+# Checking PATH version is not sufficient: a system-installed nim of the right version
+# won't have its stdlib at ${NIM_DEST}/lib/, causing downstream compilation failures.
+if [ -f "${NIM_DEST}/lib/system.nim" ]; then
+  echo "Nim ${NIM_VERSION} already installed at ${NIM_DEST}, re-linking binaries."
+  mkdir -p "${HOME}/.nimble/bin"
+  for bin_path in "${NIM_DEST}/bin/"*; do
+    ln -sf "${bin_path}" "${HOME}/.nimble/bin/$(basename "${bin_path}")"
+  done
   exit 0
 fi
 
-if [ -n "${nim_ver}" ]; then
-  newer=$(printf '%s\n%s\n' "${NIM_VERSION}" "${nim_ver}" | sort -V | tail -1)
-  if [ "${newer}" = "${nim_ver}" ]; then
-    echo "WARNING: Nim ${nim_ver} is installed; this repo is validated against ${NIM_VERSION}." >&2
-    echo "WARNING: The build will proceed but may behave differently." >&2
-    exit 0
-  fi
+nim_ver=$(nim --version 2>/dev/null | head -1 | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' | head -1 || true)
+if [ -n "${nim_ver}" ] && [ "${nim_ver}" != "${NIM_VERSION}" ]; then
+  echo "INFO: Nim ${nim_ver} found in PATH; installing Nim ${NIM_VERSION} to ${NIM_DEST}." >&2
 fi
 
 OS=$(uname -s | tr 'A-Z' 'a-z' | sed 's/darwin/macosx/')
 ARCH=$(uname -m | sed 's/x86_64/x64/;s/aarch64/arm64/')
 
-NIM_DEST="${HOME}/.nim/nim-${NIM_VERSION}"
 BINARY_URL="https://nim-lang.org/download/nim-${NIM_VERSION}-${OS}_${ARCH}.tar.xz"
 WORK_DIR=$(mktemp -d)
 trap 'rm -rf "${WORK_DIR}"' EXIT
@@ -48,9 +50,7 @@ if [ "${HTTP_STATUS}" = "200" ]; then
   echo "Downloading pre-built binary from ${BINARY_URL}..."
   curl -fL "${BINARY_URL}" -o "${WORK_DIR}/nim.tar.xz"
   tar -xJf "${WORK_DIR}/nim.tar.xz" -C "${WORK_DIR}"
-  rm -rf "${NIM_DEST}"
-  mkdir -p "${HOME}/.nim"
-  cp -r "${WORK_DIR}/nim-${NIM_VERSION}" "${NIM_DEST}"
+  SRC_DIR="${WORK_DIR}/nim-${NIM_VERSION}"
 else
   echo "No pre-built binary found for ${OS}_${ARCH}. Building from source..."
   SRC_URL="https://github.com/nim-lang/Nim/archive/refs/tags/v${NIM_VERSION}.tar.gz"
@@ -58,15 +58,19 @@ else
   tar -xzf "${WORK_DIR}/nim-src.tar.gz" -C "${WORK_DIR}"
   cd "${WORK_DIR}/Nim-${NIM_VERSION}"
   sh build_all.sh
-  rm -rf "${NIM_DEST}"
-  mkdir -p "${HOME}/.nim"
-  cp -r "${WORK_DIR}/Nim-${NIM_VERSION}" "${NIM_DEST}"
+  SRC_DIR="${WORK_DIR}/Nim-${NIM_VERSION}"
 fi
 
+# rm -rf can fail with "Directory not empty" on overlay filesystems (e.g. Docker).
+# Using cp -r src/. dst/ handles both cases: dst absent (clean) or partially present.
+rm -rf "${NIM_DEST}" 2>/dev/null || true
+mkdir -p "${NIM_DEST}"
+cp -r "${SRC_DIR}/." "${NIM_DEST}/"
+
 mkdir -p "${HOME}/.nimble/bin"
 for bin_path in "${NIM_DEST}/bin/"*; do
   ln -sf "${bin_path}" "${HOME}/.nimble/bin/$(basename "${bin_path}")"
 done
 
 echo "Nim ${NIM_VERSION} installed to ${NIM_DEST}"
-echo "Binaries symlinked in ~/.nimble/bin — ensure it is in your PATH."
+echo "Binaries symlinked in ~/.nimble/bin — ensure it is in your PATH."
\ No newline at end of file