util: Add a "command" unit test for the m5 utility.

This tests the common "command" machinery, but not the individual
commands themselves.

Change-Id: I92769b4cef8210458786e60fd3c01e8e787fb9b2
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/27563
Maintainer: Gabe Black <gabeblack@google.com>
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Jason Lowe-Power <power.jg@gmail.com>

util/m5/src/SConscript.native

@@ -27,3 +27,4 @@ Import('*')
 
 env.GTest('args')
 env.GTest('call_type')
+env.GTest('command', 'command.test.cc', 'command.cc', 'args.cc')

util/m5/src/command.test.cc

@@ -0,0 +1,161 @@
+/*
+ * Copyright 2020 Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <gtest/gtest.h>
+
+// For EXPECT_THAT and HasSubstr
+#include <gmock/gmock.h>
+
+#include "args.hh"
+#include "command.hh"
+
+bool ran_test1 = false;
+
+// A dummy class so we can make a reference to pass around.
+class DispatchTable {};
+
+DispatchTable dt;
+
+void
+do_test1(const DispatchTable &dt, Args &args)
+{
+    ran_test1 = true;
+}
+
+bool ran_test2 = false;
+
+void
+do_test2(const DispatchTable &dt, Args &args)
+{
+    ran_test2 = true;
+}
+
+TEST(CommandTest, OneCommandNoArgs)
+{
+    Command test1("test1", 0, 0, do_test1, "");
+
+    // Try to run the command with an extra argument, expecting it to fail.
+    EXPECT_FALSE(ran_test1);
+    Args args1({ "test1", "extra" });
+    EXPECT_FALSE(Command::run(dt, args1));
+    EXPECT_FALSE(ran_test1);
+
+    // Try to run with an unrecognized command.
+    Args args2({ "bad_command" });
+    EXPECT_FALSE(Command::run(dt, args2));
+    EXPECT_FALSE(ran_test1);
+
+    // Run with the right name and number of arguments.
+    Args args3({ "test1" });
+    EXPECT_TRUE(Command::run(dt, args3));
+    EXPECT_TRUE(ran_test1);
+    ran_test1 = false;
+
+    // Try with no command at all.
+    Args args4({});
+    EXPECT_FALSE(Command::run(dt, args4));
+    EXPECT_FALSE(ran_test1);
+}
+
+TEST(CommandTest, OneCommandSomeArgs)
+{
+    Command test1("test1", 2, 3, do_test1, "");
+
+    // Too few arguments.
+    EXPECT_FALSE(ran_test1);
+    Args args1({ "test1" });
+    EXPECT_FALSE(Command::run(dt, args1));
+    EXPECT_FALSE(ran_test1);
+
+    // Too many arguments.
+    Args args2({ "test1", "arg1", "arg2", "arg3", "arg4" });
+    EXPECT_FALSE(Command::run(dt, args2));
+    EXPECT_FALSE(ran_test1);
+
+    // Just enough arguments.
+    Args args3({ "test1", "arg1", "arg2" });
+    EXPECT_TRUE(Command::run(dt, args3));
+    EXPECT_TRUE(ran_test1);
+    ran_test1 = false;
+
+    // Almost too many arguments.
+    Args args4({ "test1", "arg1", "arg2", "arg3" });
+    EXPECT_TRUE(Command::run(dt, args4));
+    EXPECT_TRUE(ran_test1);
+    ran_test1 = false;
+}
+
+TEST(CommandTest, TwoCommands)
+{
+    Command test1("test1", 0, 0, do_test1, "");
+    Command test2("test2", 1, 1, do_test2, "");
+
+    // Try a bad command name.
+    Args args1({ "bad_command" });
+    EXPECT_FALSE(Command::run(dt, args1));
+    EXPECT_FALSE(ran_test1);
+    EXPECT_FALSE(ran_test2);
+
+    // Try the right command with the wrong number of arguments.
+    Args args2({ "test1", "arg1" });
+    EXPECT_FALSE(Command::run(dt, args2));
+    EXPECT_FALSE(ran_test1);
+    EXPECT_FALSE(ran_test2);
+
+    // Run the first command.
+    Args args3({ "test1" });
+    EXPECT_TRUE(Command::run(dt, args3));
+    EXPECT_TRUE(ran_test1);
+    EXPECT_FALSE(ran_test2);
+    ran_test1 = ran_test2 = false;
+
+    // Run the second command.
+    Args args4({ "test2", "arg1" });
+    EXPECT_TRUE(Command::run(dt, args4));
+    EXPECT_FALSE(ran_test1);
+    EXPECT_TRUE(ran_test2);
+    ran_test1 = ran_test2 = false;
+}
+
+TEST(CommandTest, Usage)
+{
+    std::string name1 = "test1";
+    std::string usage1 = "first test usage string";
+    std::string name2 = "test2";
+    std::string usage2 = "second test usage string";
+
+    Command test1(name1, 0, 0, do_test1, usage1);
+    Command test2(name2, 0, 0, do_test2, usage2);
+
+    auto summary = Command::usageSummary();
+
+    EXPECT_THAT(summary, testing::HasSubstr(name1));
+    EXPECT_THAT(summary, testing::HasSubstr(usage1));
+
+    EXPECT_THAT(summary, testing::HasSubstr(name2));
+    EXPECT_THAT(summary, testing::HasSubstr(usage2));
+}