Do not mutate during compilation unless an mml file is specified.

init.sh

@@ -136,6 +136,12 @@ cd "$DIR_REPOS" && ./get_repos.sh
 #
 # Download Major
 #
+# Adapt Major's default wrapper scripts:
+# - set headless to true to support Chart on machines without X.
+# - do not mutate code unless an MML is specified (for historical reasons,
+#   major v1 was sometimes called without specifying an MML to simply act as
+#   javac; Major v2+'s default is to generate all mutants as opposed to none).
+#
 echo
 echo "Setting up Major ... "
 MAJOR_VERSION="3.0.0"
@@ -145,7 +151,9 @@ cd "$BASE" && rm -rf major \
            && download_url_and_unzip "$MAJOR_URL/$MAJOR_ZIP" \
            && rm "$MAJOR_ZIP" \
            && perl -pi -e '$_ .= qq(    -Djava.awt.headless=true \\\n) if /CodeCacheSize/' \
-                major/bin/ant # Support Chart on machines without X.
+                major/bin/ant \
+           && perl -pi -e '$_ .= qq(\nif [ -z "\$MML" ]; then javac \$*; exit \$?; fi\n) if /REFACTOR=/' \
+                major/bin/major \
 
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 #