Mock Java 8 toolchain so sibling test works on arm runners

Author: smowton

java/ql/integration-tests/all-platforms/java/buildless-sibling-projects/test.py

@@ -14,11 +14,19 @@
 toolchains_dir = tempfile.mkdtemp(prefix="integration-tests-toolchains-")
 toolchains_file = os.path.join(toolchains_dir, "toolchains.xml")
 
+def none_or_blank(s):
+  return s is None or s == ""
+
 with open(toolchains_file, "w") as f:
   f.write('<?xml version="1.0" encoding="UTF-8"?>\n<toolchains>\n')
 
   for v in [8, 11, 17, 21]:
     homedir = os.getenv("JAVA_HOME_%d_X64" % v)
+    if none_or_blank(homedir):
+      homedir = os.getenv("JAVA_HOME_%d_arm64" % v)
+    if none_or_blank(homedir) and v == 8 and not none_or_blank(os.getenv("JAVA_HOME_11_arm64")):
+      print("Mocking a toolchain entry using Java 11 install as a fake Java 8 entry, so this test behaves the same on x64 and arm64 runners", file = sys.stderr)
+      homedir = os.getenv("JAVA_HOME_11_arm64")
     if homedir is not None and homedir != "":
       f.write("""
         <toolchain>