Update Cursor version resolution to avoid latest lagging behind newly published patch releases.

README.md

@@ -95,6 +95,25 @@ The `update-cursor.sh` script provides:
 - **x86_64 AppImage Download**: `https://api2.cursor.sh/updates/download/golden/linux-x64/cursor/{version}`
 - **aarch64 AppImage Download**: `https://api2.cursor.sh/updates/download/golden/linux-arm64/cursor/{version}`
 
+### Version pointers / "channels"
+
+Cursor exposes a few redirect-style pointers that may not always move in lockstep:
+
+- **`.../cursor/latest`**: “promoted” latest build for that channel. This can lag a new release during phased rollout / promotion.
+- **`.../cursor/{major.minor}` (e.g. `.../cursor/2.2`)**: latest patch within that major.minor line. This can point to a newer build earlier than `latest`.
+
+Concrete example (this has happened in practice):
+
+- `.../cursor/latest` redirects to **`Cursor-2.2.43-...AppImage`**
+- `.../cursor/2.2` redirects to **`Cursor-2.2.44-...AppImage`**
+
+In that situation, **`latest` is behind**. This flake’s updater checks both and will choose **2.2.44**.
+
+This flake’s `update-cursor.sh` default (**auto**) strategy:
+
+- **Checks multiple pointers**: `latest`, the current installed major.minor (e.g. `2.2`), and (if different) `latest`’s own major.minor (e.g. `2.3`).
+- **Picks the highest semver**: so it won’t stick to an old minor, but it also won’t miss patch releases when `latest` lags.
+
 ## Testing
 
 ```bash

update-cursor.sh

@@ -3,7 +3,11 @@
 set -euo pipefail
 
 # Script to manually update Cursor version/hashes used by the flake
-# Usage: ./update-cursor.sh [version]
+# Usage:
+#   ./update-cursor.sh                # auto: pick highest of ("latest" pointer, current major.minor pointer)
+#   ./update-cursor.sh 2.2.44         # pin exact version
+#   ./update-cursor.sh latest         # follow the "latest" pointer only
+#   ./update-cursor.sh 2.2            # follow a major.minor pointer only
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 RELEASE_FILE="$SCRIPT_DIR/cursor-release.nix"
@@ -11,26 +15,63 @@ RELEASE_FILE="$SCRIPT_DIR/cursor-release.nix"
 CHANNEL_FOR_SYSTEM_x86_64_linux="linux-x64"
 CHANNEL_FOR_SYSTEM_aarch64_linux="linux-arm64"
 
-# Function to get latest version from API redirect
+# Get a redirect URL for a given "track" pointer (e.g. latest, 2.2).
+get_redirect_url() {
+    local track="${1:?track is required}"
+    local url="https://api2.cursor.sh/updates/download/golden/linux-x64/cursor/${track}"
+
+    # Avoid stale CDN/proxy cache results for fast-moving pointers like "latest".
+    curl -sS -I \
+        -H 'Cache-Control: no-cache' \
+        -H 'Pragma: no-cache' \
+        "$url" \
+      | awk 'BEGIN{IGNORECASE=1} $1=="location:" {print $2; exit}' \
+      | tr -d '\r\n'
+}
+
+# Resolve a track pointer (e.g. latest, 2.2) into an actual semver (e.g. 2.2.44).
 get_latest_version() {
-    # Get the redirect URL and extract version from the AppImage filename
+    local track="${1:-latest}"
+
     local redirect_url
-    redirect_url=$(curl -s -I "https://api2.cursor.sh/updates/download/golden/linux-x64/cursor/latest" | grep -i location | cut -d' ' -f2 | tr -d '\r\n')
+    redirect_url="$(get_redirect_url "$track")"
 
     if [[ -n "$redirect_url" ]]; then
-        # Extract version from URL like: .../Cursor-1.7.39-x86_64.AppImage
+        # Extract version from URL like: .../Cursor-2.2.44-x86_64.AppImage
-        echo "$redirect_url" | grep -o 'Cursor-[0-9]\+\.[0-9]\+\.[0-9]\+' | sed 's/Cursor-//'
+        echo "$redirect_url" | grep -Eo 'Cursor-[0-9]+\.[0-9]+\.[0-9]+' | sed 's/Cursor-//'
     else
-        echo "Error: Could not get redirect URL"
+        echo "Error: Could not get redirect URL for track: $track" >&2
         return 1
     fi
 }
 
+# True if arg looks like a full semver (e.g. 2.2.44).
+is_full_semver() {
+    [[ "${1:-}" =~ ^[0-9]+\.[0-9]+\.[0-9]+$ ]]
+}
+
+# True if arg looks like a pointer we can resolve (e.g. latest, 2.2).
+is_pointer() {
+    [[ "${1:-}" == "latest" || "${1:-}" =~ ^[0-9]+\.[0-9]+$ ]]
+}
+
 # Function to get current version from cursor-release.nix
 get_current_version() {
     grep -o 'version = "[^"]*"' "$RELEASE_FILE" | head -1 | cut -d'"' -f2
 }
 
+# Derive major.minor track from a full version (e.g. 2.2.43 -> 2.2).
+get_track_from_version() {
+    local version="${1:?version is required}"
+    echo "$version" | awk -F. '{print $1 "." $2}'
+}
+
+# Return the highest of the provided dotted versions using natural version sort.
+semver_max() {
+    # Accepts N args; prints the max.
+    printf '%s\n' "$@" | grep -E '^[0-9]+\.[0-9]+\.[0-9]+$' | sort -V | tail -n1
+}
+
 # Function to compute sha256 for a given system+version
 prefetch_sha256() {
     local system="$1"
@@ -126,11 +167,39 @@ main() {
     
     # Determine target version
     if [[ -n "$target_version" ]]; then
-        echo "Target version: $target_version"
+        if is_full_semver "$target_version"; then
+            echo "Target version (pinned): $target_version"
+        elif is_pointer "$target_version"; then
+            echo "Target pointer: $target_version"
+            target_version="$(get_latest_version "$target_version")"
+            echo "Resolved version: $target_version"
         else
-        echo "Fetching latest version..."
+            echo "Error: Invalid argument: $target_version" >&2
-        target_version=$(get_latest_version)
+            echo "Expected: full version (e.g. 2.2.44) or pointer (latest or 2.2)" >&2
-        echo "Latest version: $target_version"
+            exit 1
+        fi
+    else
+        # Auto mode:
+        # - Check "latest" to allow moving to new major/minor (e.g. 2.3.x)
+        # - Check current major.minor line to avoid missing patches when "latest" lags (e.g. 2.2.44 vs latest=2.2.43)
+        # - Also check latest's own major.minor line (if latest=2.3.0 but 2.3 pointer is 2.3.1)
+        local current_track v_latest latest_track v_latest_track v_current_track
+        current_track="$(get_track_from_version "$current_version")"
+
+        echo "Fetching pointers: latest, $current_track"
+        v_latest="$(get_latest_version latest)"
+        latest_track="$(get_track_from_version "$v_latest")"
+        v_current_track="$(get_latest_version "$current_track")"
+
+        if [[ "$latest_track" != "$current_track" ]]; then
+            echo "Latest is on a different minor: $latest_track (also checking it)"
+            v_latest_track="$(get_latest_version "$latest_track")"
+        else
+            v_latest_track="$v_latest"
+        fi
+
+        target_version="$(semver_max "$v_latest" "$v_current_track" "$v_latest_track")"
+        echo "Resolved: latest=$v_latest pointer($current_track)=$v_current_track pointer($latest_track)=$v_latest_track -> chosen=$target_version"
     fi
     
     # Check if update is needed