[macOS] Separate xcode command line tools installation & Xcode 12.1 for Big Sur (#1815)

* add retry logic, remove separate macOS11 installation

* move to separate file

images/macos/provision/core/homebrew.sh

@@ -1,23 +1,19 @@
-#!/bin/sh
+#!/bin/bash -e -o pipefail
+
 echo "Installing Homebrew..."
-
-source ~/utils/utils.sh
-
-echo Installing Homebrew...
 HOMEBREW_INSTALL_URL="https://raw.githubusercontent.com/Homebrew/install/master/install.sh"
-
 /bin/bash -c "$(curl -fsSL ${HOMEBREW_INSTALL_URL})"
 
-echo Disabling Homebrew analytics...
+echo "Disabling Homebrew analytics..."
 brew analytics off
 
-echo Installing the last version of curl
+echo "Installing the latest curl..."
 brew install curl
 
-echo Installing wget...
+echo "Installing wget..."
 brew install wget
 
-echo Installing jq
+echo "Installing jq..."
 brew install jq
 
 # init brew bundle feature

images/macos/provision/core/xcode-clt.sh

@@ -0,0 +1,43 @@
+#!/bin/bash -e -o pipefail
+
+is_clt_installed() {
+    clt_path=`xcode-select -p 2>&1`
+    [[ -d "$clt_path" ]]
+}
+
+install_clt() {
+    echo "Searching online for the Command Line Tools"
+    # This temporary file prompts the 'softwareupdate' utility to list the Command Line Tools
+    clt_placeholder="/tmp/.com.apple.dt.CommandLineTools.installondemand.in-progress"
+    sudo touch $clt_placeholder
+    clt_label_command="/usr/sbin/softwareupdate -l |
+                        grep -B 1 -E 'Command Line Tools' |
+                        awk -F'*' '/^ *\\*/ {print \$2}' |
+                        sed -e 's/^ *Label: //' -e 's/^ *//' |
+                        sort -V |
+                        tail -n1"
+    clt_label=$(eval $clt_label_command) || true
+    if [[ -n "$clt_label" ]]; then
+        echo "Installing $clt_label"
+        sudo "/usr/sbin/softwareupdate" "-i" "$clt_label"
+    fi
+    sudo "/bin/rm" "-f" "$clt_placeholder"
+}
+
+echo "Installing Command Line Tools..."
+install_clt
+
+# Retry the installation if tools are not installed from the first attempt
+retries=30
+sleepInterval=60
+while ! is_clt_installed; do
+    if [[ $retries -eq 0 ]]; then
+        echo "Unable to find the Command Line Tools, all the attempts exhausted"
+        exit 1
+    fi
+    echo "Command Line Tools not found, trying to install them via softwareupdates, $retries attempts left"
+    install_clt
+    ((retries--))
+    echo "Wait $sleepInterval seconds before the next check for installed Command Line Tools"
+    sleep $sleepInterval
+done

images/macos/provision/core/xcode-ctl.sh

@@ -1,19 +0,0 @@
-#!/bin/bash
-
-# Homebrew doesn't support installation of command line tools on MacOS 11.0
-# https://github.com/Homebrew/install/blob/master/install.sh#L191
-# Copy-paste script from brew installation process
-# https://github.com/Homebrew/install/blob/master/install.sh#L530
-# This temporary file prompts the 'softwareupdate' utility to list the Command Line Tools
-
-clt_placeholder="/tmp/.com.apple.dt.CommandLineTools.installondemand.in-progress"
-touch $clt_placeholder
-clt_label=`/usr/sbin/softwareupdate -l |
-                      grep -B 1 -E 'Command Line Tools beta 5' |
-                      awk -F'*' '/^ *\\*/ {print \$2}' |
-                      sed -e 's/^ *Label: //' -e 's/^ *//' |
-                      sort -V |
-                      tail -n1`
-/usr/sbin/softwareupdate -i "$clt_label"
-rm -f $clt_placeholder
-sudo xcode-select --switch "/Library/Developer/CommandLineTools/"

images/macos/templates/macOS-10.13.json

@@ -128,6 +128,7 @@
             "execute_command": "chmod +x {{ .Path }}; {{ .Vars }} {{ .Path }}",
             "pause_before": "30s",
             "scripts": [
+                "./provision/core/xcode-clt.sh",
                 "./provision/core/homebrew.sh",
                 "./provision/core/dotnet.sh",
                 "./provision/core/python.sh",

images/macos/templates/macOS-10.14.json

@@ -128,6 +128,7 @@
             "execute_command": "chmod +x {{ .Path }}; {{ .Vars }} {{ .Path }}",
             "pause_before": "30s",
             "scripts": [
+                "./provision/core/xcode-clt.sh",
                 "./provision/core/homebrew.sh",
                 "./provision/core/dotnet.sh",
                 "./provision/core/python.sh",

images/macos/templates/macOS-10.15.json

@@ -129,6 +129,7 @@
             "execute_command": "chmod +x {{ .Path }}; {{ .Vars }} {{ .Path }}",
             "pause_before": "30s",
             "scripts": [
+                "./provision/core/xcode-clt.sh",
                 "./provision/core/homebrew.sh",
                 "./provision/core/dotnet.sh",
                 "./provision/core/python.sh",

images/macos/templates/macOS-11.0.json

@@ -129,7 +129,7 @@
             "execute_command": "chmod +x {{ .Path }}; {{ .Vars }} {{ .Path }}",
             "pause_before": "30s",
             "scripts": [
-                "./provision/core/xcode-ctl.sh",
+                "./provision/core/xcode-clt.sh",
                 "./provision/core/homebrew.sh",
                 "./provision/core/dotnet.sh",
                 "./provision/core/python.sh",

images/macos/toolsets/toolset-11.0.json

@@ -2,7 +2,7 @@
     "xcode": {
         "default": "11.7",
         "versions": [
-            "12.2_beta", "11.7"
+            "12.2_beta", "12.1_GM_seed", "11.7"
         ]
     },
     "xamarin": {