Update logic that handles HOMEBREW_GIT_PATH.

Library/Homebrew/brew.sh

@@ -351,7 +351,7 @@ else
   if [[ $(numeric "${curl_name_and_version##* }") -lt $(numeric "$HOMEBREW_MINIMUM_CURL_VERSION") ]]
   then
       message="Please update your system cURL.
-Minimum required version: ${HOMEBREW_MINIMUM_CURL_VERSION}.
+Minimum required version: ${HOMEBREW_MINIMUM_CURL_VERSION}
 Your cURL version: ${curl_name_and_version##* }
 Your cURL executable: $(type -p $HOMEBREW_CURL)"
 
@@ -376,16 +376,18 @@ Your cURL executable: $(type -p $HOMEBREW_CURL)"
   IFS=. read -r major minor micro build extra <<< "${git_version_output##* }"
   if [[ $(numeric "$major.$minor.$micro.$build") -lt $(numeric "$HOMEBREW_MINIMUM_GIT_VERSION") ]]
   then
-    if [[ -z $HOMEBREW_GIT_PATH ]]; then
+    message="Please update your system Git.
+Minimum required version: ${HOMEBREW_MINIMUM_GIT_VERSION}.
+Your Git version: $major.$minor.$micro.$build
+Your Git executable: $(unset git && type -p $HOMEBREW_GIT)"
+    if [[ -z $HOMEBREW_GIT_PATH || -z $HOMEBREW_DEVELOPER ]]; then
       HOMEBREW_FORCE_BREWED_GIT="1"
+      if [[ -z $HOMEBREW_GIT_WARNING ]]; then
+        onoe "$message"
+        HOMEBREW_GIT_WARNING=1
+      fi
     else
-      odie <<EOS
-The version of Git that you provided to Homebrew using HOMEBREW_GIT_PATH is too old.
-Minimum required version: ${HOMEBREW_MINIMUM_GIT_VERSION}.
-Your Git version: $major.$minor.$micro.$build.
-Please point Homebrew to Git ${HOMEBREW_MINIMUM_CURL_VERSION} or newer
-or unset HOMEBREW_GIT_PATH variable.
-EOS
+      odie "$message"
     fi
   fi
 
@@ -424,6 +426,7 @@ export HOMEBREW_CURL
 export HOMEBREW_CURL_WARNING
 export HOMEBREW_SYSTEM_CURL_TOO_OLD
 export HOMEBREW_GIT
+export HOMEBREW_GIT_WARNING
 export HOMEBREW_MINIMUM_GIT_VERSION
 export HOMEBREW_PROCESSOR
 export HOMEBREW_PRODUCT

Library/Homebrew/cmd/update.sh

@@ -373,7 +373,7 @@ EOS
       ! -x "$HOMEBREW_PREFIX/opt/curl/bin/curl" ]]
   then
     # we cannot install a Homebrew cURL if homebrew/core is unavailable.
-    if [[ -d "$HOMEBREW_LIBRARY/Taps/homebrew/homebrew-core" ]] && ! brew install curl
+    if [[ ! -d "$HOMEBREW_LIBRARY/Taps/homebrew/homebrew-core" ]] || ! brew install curl
     then
       odie "Curl must be installed and in your PATH!"
     fi
@@ -384,7 +384,7 @@ EOS
       ! -x "$HOMEBREW_PREFIX/opt/git/bin/git" ]]
   then
     # we cannot install a Homebrew Git if homebrew/core is unavailable.
-    if [[ -d "$HOMEBREW_LIBRARY/Taps/homebrew/homebrew-core" ]] && ! brew install git
+    if [[ ! -d "$HOMEBREW_LIBRARY/Taps/homebrew/homebrew-core" ]] || ! brew install git
     then
       odie "Git must be installed and in your PATH!"
     fi