From 13f6d4b71a194f74001f7a6fbe92bbb2c5c62813 Mon Sep 17 00:00:00 2001
From: Mathias Preiner <mathias.preiner@gmail.com>
Date: Fri, 2 Aug 2019 13:49:03 -0700
Subject: [PATCH] Add better Python detection for contrib scripts. (#3150)

---
 contrib/get-antlr-3.4        |  4 ++--
 contrib/get-script-header.sh | 16 ++++++++++++++--
 2 files changed, 16 insertions(+), 4 deletions(-)

diff --git a/contrib/get-antlr-3.4 b/contrib/get-antlr-3.4
index 6bfa18c46..a3dfb410d 100755
--- a/contrib/get-antlr-3.4
+++ b/contrib/get-antlr-3.4
@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 source "$(dirname "$0")/get-script-header.sh"
 ANTLR_HOME_DIR=antlr-3.4
@@ -46,7 +46,7 @@ cd libantlr3c-3.4
 
 # Use an absolute path for the installation directory to avoid spurious libtool
 # warnings about the ANTLR library having moved
-PREFIX=$(python -c "import os; print(os.path.realpath('$(pwd)/../..'))")
+PREFIX=$($PYTHON -c "import os; print(os.path.realpath('$(pwd)/../..'))")
 
 # Make antlr3debughandlers.c empty to avoid unreferenced symbols
 rm -rf src/antlr3debughandlers.c && touch src/antlr3debughandlers.c
diff --git a/contrib/get-script-header.sh b/contrib/get-script-header.sh
index de4a93587..e5b708042 100644
--- a/contrib/get-script-header.sh
+++ b/contrib/get-script-header.sh
@@ -1,6 +1,6 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
-set -e
+set -e -o pipefail
 
 cd "$(dirname "$0")/.."
 
@@ -24,3 +24,15 @@ function webget {
     exit 1
   fi
 }
+
+for cmd in python python2 python3; do
+  if [ -x "$(command -v $cmd)" ]; then
+    PYTHON="$cmd"
+    break
+  fi
+done
+
+if [ -z "$PYTHON" ]; then
+  echo "Error: Couldn't find python, python2, or python3." >&2
+  exit 1
+fi
-- 
2.30.2