Option to test a local BouncyCastle jar (#16)

Resolves Github issue #4

BUILD

@@ -38,6 +38,14 @@ bouncycastle_all_tests(
     deps = common_deps,
 )
 
+java_test(
+    name = "BouncyCastleAllTestsLocal",
+    size = "large",
+    srcs = ["java/com/google/security/wycheproof/BouncyCastleAllTests.java"] + test_srcs,
+    test_class = "com.google.security.wycheproof.BouncyCastleAllTests",
+    deps = common_deps + ["@local//:bouncycastle_jar"],
+)
+
 # Generates SpongyCastleAllTests_1_xx target for all available versions,
 # plus a SpongyCastleAllTests alias for latest stable.
 #
@@ -79,6 +87,14 @@ bouncycastle_tests(
     deps = common_deps,
 )
 
+java_test(
+    name = "BouncyCastleTestLocal",
+    size = "large",
+    srcs = ["java/com/google/security/wycheproof/BouncyCastleTest.java"] + test_srcs,
+    test_class = "com.google.security.wycheproof.BouncyCastleTest",
+    deps = common_deps + ["@local//:bouncycastle_jar"],
+)
+
 # Generates SpongyCastleTest_1_xx target for all available versions,
 # plus a SpongyCastleTest alias for latest stable.
 #

README.md

@@ -110,6 +110,26 @@ bazel test BouncyCastleAllTests_1_52
 bazel test BouncyCastleAllTests_*
 ```
 
+- To test a local jar, set the `WYCHEPROOF_BOUNCYCASTLE_JAR` environment variable:
+
+``` shell
+$ WYCHEPROOF_BOUNCYCASTLE_JAR=/path/to/bouncycastle
+$ bazel test BouncyCastleTestLocal
+$ bazel test BouncyCastleAllTestsLocal
+```
+
+Note: bazel does not currently invalidate the build on environment changes. If
+you change the `WYCHEPROOF_BOUNCYCASTLE_JAR` environment variable, run `bazel
+clean` to force a rebuild:
+
+``` shell
+$ WYCHEPROOF_BOUNCYCASTLE_JAR=/path/to/bouncycastle
+$ bazel test BouncyCastleTestLocal
+$ WYCHEPROOF_BOUNCYCASTLE_JAR=/path/to/other/jar
+$ bazel clean
+$ bazel test BouncyCastleTestLocal
+```
+
 - To test [Spongy Castle](https://rtyley.github.io/spongycastle/), replace
 BouncyCastle with SpongyCastle in your commands, for example
 

WORKSPACE

@@ -97,3 +97,7 @@ maven_jar(
     name = "spongycastle_prov_1_54",
     artifact = "com.madgag.spongycastle:prov:1.54.0.0",
 )
+
+load(":local_repository_defs.bzl", "local_jars")
+
+local_jars(name = "local")

local_repository_defs.bzl

@@ -0,0 +1,25 @@
+_bouncycastle_jar_rule = """
+java_import(
+    name = "bouncycastle_jar",
+    jars = ["bouncycastle.jar"],
+    visibility = ["//visibility:public"],
+ )
+"""
+
+# TODO(ekasper): implement environment invalidation once supported by bazel,
+# see https://bazel.build/designs/2016/10/18/repository-invalidation.html
+# Meanwhile, users have to call 'bazel clean' explicitly when the
+# environment changes.
+def _local_jars_impl(repository_ctx):
+  contents = ""
+  if "WYCHEPROOF_BOUNCYCASTLE_JAR" in repository_ctx.os.environ:
+    repository_ctx.symlink(repository_ctx.os.environ["WYCHEPROOF_BOUNCYCASTLE_JAR"],
+                           "bouncycastle.jar")
+    contents += _bouncycastle_jar_rule
+
+  repository_ctx.file("BUILD", contents)
+
+local_jars = repository_rule(
+    implementation = _local_jars_impl,
+    local = True
+)