From 1c757cce34344dfecc9a724034680225143f92b7 Mon Sep 17 00:00:00 2001
From: Bruno de Oliveira Abinader <bruno@mapbox.com>
Date: Wed, 22 Mar 2017 15:42:35 +0200
Subject: [PATCH] [build] Autodetect Qt{4,5}

---
 .travis.yml                 |  2 +-
 Makefile                    | 20 ++++++++++++--------
 platform/qt/bitrise-qt4.yml |  1 -
 scripts/check-qt.sh         |  9 +++++++++
 4 files changed, 22 insertions(+), 10 deletions(-)
 create mode 100755 scripts/check-qt.sh

diff --git a/.travis.yml b/.travis.yml
index 256e6a2aa..cc7f71549 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -166,7 +166,7 @@ matrix:
       dist: trusty
       language: cpp
       compiler: "qt4-gcc5-release"
-      env: BUILDTYPE=Release _CXX=g++-5 _CC=gcc-5 WITH_QT_4=1
+      env: BUILDTYPE=Release _CXX=g++-5 _CC=gcc-5
       addons: *qt4
       before_script:
         - mapbox_start_xvfb
diff --git a/Makefile b/Makefile
index 0edfe685a..2eb2728b8 100644
--- a/Makefile
+++ b/Makefile
@@ -361,20 +361,23 @@ endif
 
 #### Qt targets #####################################################
 
-ifeq ($(WITH_QT_4), 1)
-QT_ROOT_PATH = build/qt4-$(BUILD_PLATFORM)-$(BUILD_PLATFORM_VERSION)
-else
-QT_ROOT_PATH = build/qt-$(BUILD_PLATFORM)-$(BUILD_PLATFORM_VERSION)
-endif
-
-ifneq (,$(shell which qmake))
-export QT_INSTALL_DOCS = $(shell qmake -query QT_INSTALL_DOCS)
+QT_QMAKE_FOUND := $(shell command -v qmake 2> /dev/null)
+ifdef QT_QMAKE_FOUND
+  export QT_INSTALL_DOCS = $(shell qmake -query QT_INSTALL_DOCS)
+  ifeq ($(shell qmake -query QT_VERSION | head -c1), 4)
+    QT_ROOT_PATH = build/qt4-$(BUILD_PLATFORM)-$(BUILD_PLATFORM_VERSION)
+    WITH_QT_4=1
+  else
+    QT_ROOT_PATH = build/qt-$(BUILD_PLATFORM)-$(BUILD_PLATFORM_VERSION)
+    WITH_QT_4=0
+  endif
 endif
 
 export QT_OUTPUT_PATH = $(QT_ROOT_PATH)/$(BUILDTYPE)
 QT_BUILD = $(QT_OUTPUT_PATH)/build.ninja
 
 $(QT_BUILD): $(BUILD_DEPS)
+	@scripts/check-qt.sh
 	mkdir -p $(QT_OUTPUT_PATH)
 	(cd $(QT_OUTPUT_PATH) && cmake -G Ninja ../../.. \
 		-DCMAKE_BUILD_TYPE=$(BUILDTYPE) \
@@ -392,6 +395,7 @@ ifeq ($(HOST_PLATFORM), macos)
 
 MACOS_QT_PROJ_PATH = $(QT_ROOT_PATH)/xcode/mbgl.xcodeproj
 $(MACOS_QT_PROJ_PATH): $(BUILD_DEPS)
+	@scripts/check-qt.sh
 	mkdir -p $(QT_ROOT_PATH)/xcode
 	(cd $(QT_ROOT_PATH)/xcode && cmake -G Xcode ../../.. \
 		-DMBGL_PLATFORM=qt \
diff --git a/platform/qt/bitrise-qt4.yml b/platform/qt/bitrise-qt4.yml
index 0a08d684f..d8c7e0788 100644
--- a/platform/qt/bitrise-qt4.yml
+++ b/platform/qt/bitrise-qt4.yml
@@ -19,7 +19,6 @@ workflows:
             brew link qt
             brew linkapps qt
             export BUILDTYPE=Debug
-            export WITH_QT_4=1
             make qt-app
             make run-qt-test
         - is_debug: 'yes'
diff --git a/scripts/check-qt.sh b/scripts/check-qt.sh
new file mode 100755
index 000000000..578003824
--- /dev/null
+++ b/scripts/check-qt.sh
@@ -0,0 +1,9 @@
+#!/usr/bin/env bash
+
+set -e
+set -o pipefail
+
+if [ ! $(command -v qmake 2> /dev/null) ]; then
+    echo "No qmake found - missing Qt development files"
+    exit 1
+fi