add tests to verify capturing output from ChildProcess

Summary: as above.

Reviewed By: sid0

Differential Revision: D4424911

fbshipit-source-id: 595457173c4b21d512a18fd17c360d529e72299b

ChildProcess.cpp

@@ -375,4 +375,9 @@ void ChildProcess::kill(
   }
 #endif
 }
+
+Pipe& ChildProcess::pipe(int fd) {
+  return *pipes_.at(fd);
+}
+
 }

ChildProcess.h

@@ -144,6 +144,8 @@ class ChildProcess {
 #endif
       );
 
+  Pipe& pipe(int fd);
+
  private:
   pid_t pid_;
   bool waited_{false};

Makefile.am

@@ -133,6 +133,7 @@ WILDMATCH_LIB = libwildmatch.a
 TESTS = \
 		tests/art.t \
 		tests/bser.t \
+		tests/childproc.t \
 		tests/ignore.t \
 		tests/pending.t \
 		tests/string.t \
@@ -213,6 +214,19 @@ tests_art_t_SOURCES = \
 	hash.cpp \
 	log.cpp
 
+tests_childproc_t_CPPFLAGS = $(THIRDPARTY_CPPFLAGS) @IRONMANCFLAGS@
+tests_childproc_t_LDADD = $(TAP_LIB) $(JSON_LIB)
+tests_childproc_t_SOURCES = \
+	tests/childproc.cpp \
+	tests/log_stub.cpp \
+	ChildProcess.cpp \
+	Pipe.cpp \
+	FileDescriptor.cpp \
+	PubSub.cpp \
+	string.cpp \
+	hash.cpp \
+	log.cpp
+
 tests_ignore_t_CPPFLAGS = $(THIRDPARTY_CPPFLAGS) @IRONMANCFLAGS@
 tests_ignore_t_LDADD = $(TAP_LIB) $(JSON_LIB)
 tests_ignore_t_SOURCES = \

TARGETS

@@ -181,6 +181,9 @@ cpp_library(
         'opendir.cpp',
         'pending.cpp',
         'time.cpp',
+        'ChildProcess.cpp',
+        'Pipe.cpp',
+        'FileDescriptor.cpp',
     ],
     deps=[
         ':headers',

tests/TARGETS

@@ -77,3 +77,11 @@ t_test(
       '@/watchman/thirdparty/wildmatch:wildmatch',
     ],
 )
+
+t_test(
+    name='childproc',
+    srcs=['childproc.cpp', 'log_stub.cpp'],
+    deps=[
+      '@/watchman:testsupport',
+    ],
+)

tests/childproc.cpp

@@ -0,0 +1,48 @@
+/* Copyright 2017-present Facebook, Inc.
+ * Licensed under the Apache License, Version 2.0. */
+#include "watchman_system.h"
+#include "ChildProcess.h"
+#include "thirdparty/tap.h"
+
+using watchman::ChildProcess;
+using Environment = ChildProcess::Environment;
+using Options = ChildProcess::Options;
+
+void test_pipe() {
+  Options opts;
+  opts.pipeStdout();
+  ChildProcess echo(
+      {
+#ifndef _WIN32
+          "/bin/echo",
+#else
+          "cmd",
+          "/c",
+          "echo",
+#endif
+          "hello"},
+      std::move(opts));
+
+  echo.pipe(STDOUT_FILENO).read.clearNonBlock();
+  echo.wait();
+
+  char buf[128];
+  auto len = read(echo.pipe(STDOUT_FILENO).read.fd(), buf, sizeof(buf));
+
+  ok(len >= 0,
+     "read from pipe was successful: len=%d err=%s",
+     len,
+     strerror(errno));
+  w_string_piece line(buf, len);
+  ok(line.startsWith("hello"), "starts with hello");
+}
+
+int main(int argc, char **argv) {
+  (void)argc;
+  (void)argv;
+
+  plan_tests(2);
+  test_pipe();
+
+  return exit_status();
+}

winbuild/Makefile

@@ -130,6 +130,7 @@ TEST_DIR_SRCS=
 TEST_DIR_SRCS_CPP=\
 	tests\art_test.cpp \
 	tests\bser.cpp \
+	tests\childproc.cpp \
 	tests\ignore_test.cpp \
 	tests\log_stub.cpp \
 	tests\log.cpp
@@ -139,7 +140,7 @@ TEST_OBJS=$(TEST_SRCS_CPP:.cpp=.obj) $(TEST_SRCS_C:.c=.obj)
 TEST_DIR_OBJS=$(TEST_DIR_SRCS:.c=.obj) $(TEST_DIR_SRCS_CPP:.cpp=.obj)
 TESTS=tests\log.exe tests\bser.exe tests\wildmatch_test.exe \
 			tests\art.exe tests\ignore.exe tests\pending.exe \
-			tests\string.exe
+			tests\string.exe tests\childproc.exe
 
 {}.cpp{}.obj::
 	@echo CXX $<
@@ -288,6 +289,22 @@ tests\bser.exe: tests\bser.obj bser.obj $(TEST_OBJS) \
 	@echo LINK $@
 	$(LINKER) $** $(LIBS)
 
+tests\childproc.exe: tests\childproc.obj $(TEST_OBJS) \
+	tests\log_stub.obj  \
+	ChildProcess.obj \
+	winbuild\posix_spawn.obj \
+	winbuild\pathmap.obj \
+	Pipe.obj \
+	FileDescriptor.obj \
+	Win32Handle.obj \
+	string.obj \
+	stream_win.obj \
+	hash.obj \
+	PubSub.obj \
+	log.obj
+	@echo LINK $@
+	$(LINKER) $** $(LIBS)
+
 tests\log.exe: tests\log.obj log.obj $(TEST_OBJS) \
 	PubSub.obj \
 	string.obj \