[lldb] [test] Use secondary pty end for testing Terminal

[mgorny]

Summary

Open and use the secondary end of a pty for testing Terminal properties
in order to fix the tests on Darwin. While at it, streamline getting
the fd and Terminal class.

[teemperor]

If Green Dragon was still with us this would make it happy (and green), so LGTM.

lldb/unittests/Host/posix/TerminalTest.cpp

 #include <termios.h>
 #include <unistd.h>
 
 using namespace lldb_private;
 
 class TerminalTest : public ::testing::Test {
 protected:
   PseudoTerminal m_pty;
+  int m_fd;
+  Terminal m_term;
 
   void SetUp() override {
-    EXPECT_THAT_ERROR(m_pty.OpenFirstAvailablePrimary(O_RDWR | O_NOCTTY),
+    ASSERT_THAT_ERROR(m_pty.OpenFirstAvailablePrimary(O_RDWR | O_NOCTTY),
                       llvm::Succeeded());
+    ASSERT_THAT_ERROR(m_pty.OpenSecondary(O_RDWR | O_NOCTTY),
+                      llvm::Succeeded());
+    m_fd = m_pty.GetSecondaryFileDescriptor();
+    ASSERT_NE(m_fd, -1);
+    m_term.SetFileDescriptor(m_fd);
   }
 };
 
 TEST_F(TerminalTest, PtyIsATerminal) {
-  Terminal term{m_pty.GetPrimaryFileDescriptor()};
-  EXPECT_EQ(term.IsATerminal(), true);
+  EXPECT_EQ(m_term.IsATerminal(), true);
 }
 
 TEST_F(TerminalTest, PipeIsNotATerminal) {
   int pipefd[2];
   ASSERT_EQ(pipe(pipefd), 0);
   Terminal pipeterm{pipefd[0]};
   EXPECT_EQ(pipeterm.IsATerminal(), false);
   close(pipefd[0]);
   close(pipefd[1]);
 }
 
 TEST_F(TerminalTest, SetEcho) {
   struct termios terminfo;
-  Terminal term{m_pty.GetPrimaryFileDescriptor()};
 
-  ASSERT_EQ(term.SetEcho(true), true);
-  ASSERT_EQ(tcgetattr(m_pty.GetPrimaryFileDescriptor(), &terminfo), 0);
+  ASSERT_EQ(m_term.SetEcho(true), true);
+  ASSERT_EQ(tcgetattr(m_fd, &terminfo), 0);
   EXPECT_NE(terminfo.c_lflag & ECHO, 0U);
 
-  ASSERT_EQ(term.SetEcho(false), true);
-  ASSERT_EQ(tcgetattr(m_pty.GetPrimaryFileDescriptor(), &terminfo), 0);
+  ASSERT_EQ(m_term.SetEcho(false), true);
+  ASSERT_EQ(tcgetattr(m_fd, &terminfo), 0);
   EXPECT_EQ(terminfo.c_lflag & ECHO, 0U);
 }
 
 TEST_F(TerminalTest, SetCanonical) {
   struct termios terminfo;
-  Terminal term{m_pty.GetPrimaryFileDescriptor()};
 
-  ASSERT_EQ(term.SetCanonical(true), true);
-  ASSERT_EQ(tcgetattr(m_pty.GetPrimaryFileDescriptor(), &terminfo), 0);
+  ASSERT_EQ(m_term.SetCanonical(true), true);
+  ASSERT_EQ(tcgetattr(m_fd, &terminfo), 0);
   EXPECT_NE(terminfo.c_lflag & ICANON, 0U);
 
-  ASSERT_EQ(term.SetCanonical(false), true);
-  ASSERT_EQ(tcgetattr(m_pty.GetPrimaryFileDescriptor(), &terminfo), 0);
+  ASSERT_EQ(m_term.SetCanonical(false), true);
+  ASSERT_EQ(tcgetattr(m_fd, &terminfo), 0);
   EXPECT_EQ(terminfo.c_lflag & ICANON, 0U);
 }
 
 TEST_F(TerminalTest, SaveRestoreRAII) {
   struct termios orig_terminfo;
   struct termios terminfo;
-  ASSERT_EQ(tcgetattr(m_pty.GetPrimaryFileDescriptor(), &orig_terminfo), 0);
-
-  Terminal term{m_pty.GetPrimaryFileDescriptor()};
+  ASSERT_EQ(tcgetattr(m_fd, &orig_terminfo), 0);
 
   {
-    TerminalState term_state{term};
+    TerminalState term_state{m_term};
     terminfo = orig_terminfo;
 
     // make an arbitrary change
     cfsetispeed(&terminfo,
                 cfgetispeed(&orig_terminfo) == B9600 ? B4800 : B9600);
     cfsetospeed(&terminfo,
                 cfgetospeed(&orig_terminfo) == B9600 ? B4800 : B9600);
 
-    ASSERT_EQ(tcsetattr(m_pty.GetPrimaryFileDescriptor(), TCSANOW, &terminfo),
+    ASSERT_EQ(tcsetattr(m_fd, TCSANOW, &terminfo),
               0);
   }
 
-  ASSERT_EQ(tcgetattr(m_pty.GetPrimaryFileDescriptor(), &terminfo), 0);
+  ASSERT_EQ(tcgetattr(m_fd, &terminfo), 0);
   ASSERT_EQ(memcmp(&terminfo, &orig_terminfo, sizeof(terminfo)), 0);
 }
 
 TEST_F(TerminalTest, SaveRestore) {
   TerminalState term_state;
 
   struct termios orig_terminfo;
   struct termios terminfo;
-  ASSERT_EQ(tcgetattr(m_pty.GetPrimaryFileDescriptor(), &orig_terminfo), 0);
+  ASSERT_EQ(tcgetattr(m_fd, &orig_terminfo), 0);
 
-  Terminal term{m_pty.GetPrimaryFileDescriptor()};
-  term_state.Save(term, false);
+  term_state.Save(m_term, false);
   terminfo = orig_terminfo;
 
   // make an arbitrary change
   cfsetispeed(&terminfo, cfgetispeed(&orig_terminfo) == B9600 ? B4800 : B9600);
   cfsetospeed(&terminfo, cfgetospeed(&orig_terminfo) == B9600 ? B4800 : B9600);
 
-  ASSERT_EQ(tcsetattr(m_pty.GetPrimaryFileDescriptor(), TCSANOW, &terminfo), 0);
+  ASSERT_EQ(tcsetattr(m_fd, TCSANOW, &terminfo), 0);
 
   term_state.Restore();
-  ASSERT_EQ(tcgetattr(m_pty.GetPrimaryFileDescriptor(), &terminfo), 0);
+  ASSERT_EQ(tcgetattr(m_fd, &terminfo), 0);
   ASSERT_EQ(memcmp(&terminfo, &orig_terminfo, sizeof(terminfo)), 0);
 }