From 3447433988c28b630659eaf6a4b06ad41ceeeae2 Mon Sep 17 00:00:00 2001
From: Rene Leonhardt <65483435+reneleonhardt@users.noreply.github.com>
Date: Sat, 1 Jun 2024 15:39:21 +0200
Subject: [PATCH] feat: Allow major or minor version lookup

---
 libexec/pyenv                    |  22 +++---
 libexec/pyenv-installed          | 120 +++++++++++++++++++++++++++++++
 libexec/pyenv-version-file-write |  53 +++++++++++---
 3 files changed, 179 insertions(+), 16 deletions(-)
 create mode 100755 libexec/pyenv-installed

diff --git a/libexec/pyenv b/libexec/pyenv
index fdea4911..ea7779c8 100755
--- a/libexec/pyenv
+++ b/libexec/pyenv
@@ -1,5 +1,6 @@
 #!/usr/bin/env bash
 set -e
+export LC_ALL=C # boost grep performance by disabling unicode
 
 if [ "$1" = "--debug" ]; then
   export PYENV_DEBUG=1
@@ -118,16 +119,21 @@ case "$command" in
   exec pyenv-help
   ;;
 * )
-  command_path="$(command -v "pyenv-$command" || true)"
-  if [ -z "$command_path" ]; then
-    if [ "$command" == "shell" ]; then
-      abort "shell integration not enabled. Run \`pyenv init' for instructions."
-    else
-      abort "no such command \`$command'"
+  # Just a version number given (or `latest` or `system`) -> assume `pyenv local $@`
+  if grep -q -E "^[0-9]+(\.[0-9]+){0,2}$" <<<"${command}" || [ "$command" == "latest" ] || [ "$command" == "system" ]; then
+    command_path="pyenv-local"
+  else
+    command_path="$(command -v "pyenv-$command" || true)"
+    if [ -z "$command_path" ]; then
+      if [ "$command" == "shell" ]; then
+        abort "shell integration not enabled. Run \`pyenv init' for instructions."
+      else
+        abort "no such command \`$command'"
+      fi
     fi
-  fi
 
-  shift 1
+    shift 1
+  fi
   if [ "$1" = --help ]; then
     if [[ "$command" == "sh-"* ]]; then
       echo "pyenv help \"$command\""
diff --git a/libexec/pyenv-installed b/libexec/pyenv-installed
new file mode 100755
index 00000000..f6c03a22
--- /dev/null
+++ b/libexec/pyenv-installed
@@ -0,0 +1,120 @@
+#!/usr/bin/env bash
+# Summary: Display an installed Python version
+# Usage: pyenv installed [<version>]
+#
+# Displays the installed Python version, searching for shortcuts if necessary.
+# If no version is given, `pyenv installed' displays the latest installed version.
+# If version is `system`, `system` will be returned if an installed system Python can be found.
+# If version is `latest`, the latest installed Python version will be returned (3.12.3).
+# If version is `3`, the latest installed Python version of this major version will be returned (3.12.3).
+# If version is `12` or `3.12`, the latest installed patch of this minor version will be returned (3.12.3).
+# If version is `3.12.3`, the same version will be returned if that patch version is installed (3.12.3).
+# If version is not found or no versions are installed, an error message will be returned with an error code.
+
+set -e
+[ -n "$PYENV_DEBUG" ] && set -x
+
+# Provide pyenv completions
+if [ "$1" = "--complete" ]; then
+  echo system
+  exec pyenv-versions --bare
+fi
+
+majors=({3,2}) # Supported Python versions: 3,2 (latest first)
+
+versions() {
+  # Sort correctly (3.10.9 comes before 3.10.10)
+  pyenv versions --bare | sort -V | $(type -p ggrep grep | head -1) -F "$query" || true
+}
+
+latest_version() {
+  versions | tail -1
+}
+
+latest_major() {
+  # 3 -> latest major 3.12.3
+  versions | grep -oE "^$(regex "$1")\\.[0-9]+\\.[0-9]+$" | tail -1
+}
+
+latest_minor() {
+  # 3.12 -> latest minor 3.12.3
+  versions | grep -oE "^$(regex "$1")\\.([0-9]+)$" | tail -1
+}
+
+installed() {
+  # 3.12.3 -> 3.12.3 if installed (else "")
+  versions | grep -oE "^$(regex "$1")$" || true
+}
+
+regex() {
+  echo "${1//\./\\.}"
+}
+
+if [ -n "$1" ]; then
+  version="$1"
+else
+  version="latest"
+fi
+
+if [ "$version" = "system" ]; then
+  if PYTHON_PATH="$(PYENV_VERSION="${version}" pyenv-which python 2>/dev/null)" || \
+      PYTHON_PATH="$(PYENV_VERSION="${version}" pyenv-which python3 2>/dev/null)" || \
+      PYTHON_PATH="$(PYENV_VERSION="${version}" pyenv-which python2 2>/dev/null)"; then
+    echo "system"
+    exit 0
+  else
+    echo "pyenv: system version not found in PATH" >&2
+    exit 1
+  fi
+fi
+if [ "$version" = "latest" ]; then
+  LATEST_PATCH=$(latest_version)
+  if [ -n "$LATEST_PATCH" ]; then
+    echo "$LATEST_PATCH"
+    exit 0
+  else
+    echo "pyenv: no versions installed" >&2
+    exit 1
+  fi
+fi
+
+# Check version=3 (major without minor and patch) => 3.12.3 (latest major version)
+# Or version=12 (minor without major and patch) => 3.12.3 (latest patch version)
+if grep -q -E "^[0-9]+(\s*)$" <<<"${version}"; then
+  for major in "${majors[@]}"; do
+    if [ "$version" = "$major" ]; then
+      LATEST_MAJOR=$(latest_major "$version")
+      if [ -n "$LATEST_MAJOR" ]; then
+        echo "$LATEST_MAJOR"
+        exit 0
+      fi
+    else
+      LATEST_MINOR=$(latest_minor "$major.$version")
+      if [ -n "$LATEST_MINOR" ]; then
+        echo "$LATEST_MINOR"
+        exit 0
+      fi
+    fi
+  done
+fi
+
+# Check version=3.12 (minor without patch) => 3.12.3 (latest patch version)
+if grep -q -E "^[0-9]+\.[0-9]+(\s*)$" <<<"${version}"; then
+  LATEST_MINOR=$(latest_minor "$version")
+  if [ -n "$LATEST_MINOR" ]; then
+    echo "$LATEST_MINOR"
+    exit 0
+  fi
+fi
+
+# Check version=3.12.3 (full version number) => 3.12.3 (installed version)
+if grep -q -E "^[0-9]+\.[0-9]+\.[0-9]+(\s*)$" <<<"${version}"; then
+  INSTALLED=$(installed "$version")
+  if [ -n "$INSTALLED" ]; then
+    echo "$INSTALLED"
+    exit 0
+  fi
+fi
+
+echo "pyenv: version \`${version}' not installed" >&2
+exit 1
diff --git a/libexec/pyenv-version-file-write b/libexec/pyenv-version-file-write
index 7095140f..92081792 100755
--- a/libexec/pyenv-version-file-write
+++ b/libexec/pyenv-version-file-write
@@ -1,5 +1,8 @@
 #!/usr/bin/env bash
+# Summary: Writes specified version(s) to the specified file if the version(s) exist
 # Usage: pyenv version-file-write <file> <version>
+# If the specified version is not installed, only display error message and return error code.
+# If only a single version="system" is specified and installed, display previous version (if any) and remove file.
 
 set -e
 [ -n "$PYENV_DEBUG" ] && set -x
@@ -13,12 +16,46 @@ if [ -z "$versions" ] || [ -z "$PYENV_VERSION_FILE" ]; then
   exit 1
 fi
 
-# Make sure the specified version is installed.
-pyenv-prefix "${versions[@]}" >/dev/null
+# Make sure the specified version(s) are installed.
+# Use pyenv-prefix loop logic.
+if [ -n "$1" ]; then
+  OLDIFS="$IFS"
+  {
+    IFS=:
+    export PYENV_VERSION="$*"
+  }
+  IFS="$OLDIFS"
+elif [ -z "$PYENV_VERSION" ]; then
+  PYENV_VERSION="$(pyenv-version-name)"
+fi
 
-# Write the version out to disk.
-# Create an empty file. Using "rm" might cause a permission error.
-> "$PYENV_VERSION_FILE"
-for version in "${versions[@]}"; do
-  echo "$version" >> "$PYENV_VERSION_FILE"
-done
+PYENV_VERSIONS=()
+OLDIFS="$IFS"
+{
+  IFS=:
+  for version in ${PYENV_VERSION}; do
+    if ! INSTALLED="$(pyenv-installed "$version" 2>&1)"; then
+      echo "$INSTALLED" >&2
+      exit 1
+    fi
+    PYENV_VERSIONS=("${PYENV_VERSIONS[@]}" "$INSTALLED")
+  done
+}
+IFS="$OLDIFS"
+
+# Special case: only system was specified and found
+if [ "$1" = "system" ]; then
+  if [ -f "$PYENV_VERSION_FILE" ]; then
+    if previous="$(head -1 "$PYENV_VERSION_FILE" | grep -E "^[0-9]+\.[0-9]+\.[0-9]+$")"; then
+      echo "pyenv: using system version instead of $previous now"
+    fi
+    rm "$PYENV_VERSION_FILE"
+  fi
+else
+  # Write the version out to disk.
+  # Create an empty file. Using "rm" might cause a permission error.
+  > "$PYENV_VERSION_FILE"
+  for version in "${PYENV_VERSIONS[@]}"; do
+    echo "$version" >> "$PYENV_VERSION_FILE"
+  done
+fi