add $pipestatus support

CHANGELOG.md

@@ -5,6 +5,7 @@
 
 ## Notable fixes and improvements
 - Fixed infinite recursion triggered if a custom `fish_title` function calls `read` interactively
+- Add `$pipestatus` support
 
 ### Syntax changes and new commands
 - None yet.

sphinx_doc_src/index.rst

@@ -1193,6 +1193,8 @@ The user can change the settings of ``fish`` by changing the values of certain v
 
 - ``status``, the `exit status <#variables-status>`_ of the last foreground job to exit. If the job was terminated through a signal, the exit status will be 128 plus the signal number.
 
+- ``pipestatus``, an array of exit statuses of all processes that made up the last executed pipe.
+
 - ``USER``, the current username. This variable can be changed by the user.
 
 - ``CMD_DURATION``, the runtime of the last command in milliseconds.

sphinx_doc_src/tutorial.rst

@@ -246,7 +246,7 @@ Unlike other shells, ``fish`` stores the exit status of the last command in ``$s
     <outp>1</outp>
 
 
-Zero is considered success, and non-zero is failure.
+Zero is considered success, and non-zero is failure. There is also a ``$pipestatus`` array variable for the exit statues of processes in a pipe.
 
 
 Exports (Shell Variables)

src/env.cpp

@@ -316,8 +316,8 @@ bool string_set_contains(const T &set, const wchar_t *val) {
 /// Check if a variable may not be set using the set command.
 static bool is_read_only(const wchar_t *val) {
     const string_set_t env_read_only = {
-        L"PWD",          L"SHLVL",    L"history",  L"status", L"version",
+        L"PWD",          L"SHLVL",    L"history",  L"pipestatus", L"status", L"version",
-        L"FISH_VERSION", L"fish_pid", L"hostname", L"_",      L"fish_private_mode"};
+        L"FISH_VERSION", L"fish_pid", L"hostname", L"_",          L"fish_private_mode"};
     return string_set_contains(env_read_only, val) ||
         (in_private_mode() && wcscmp(L"fish_history", val) == 0);
 }
@@ -330,7 +330,7 @@ static bool variable_should_auto_pathvar(const wcstring &name) {
 }
 
 /// Table of variables whose value is dynamically calculated, such as umask, status, etc.
-static const string_set_t env_electric = {L"history", L"status", L"umask"};
+static const string_set_t env_electric = {L"history", L"pipestatus", L"status", L"umask"};
 
 static bool is_electric(const wcstring &key) { return contains(env_electric, key); }
 
@@ -1391,6 +1391,14 @@ maybe_t<env_var_t> env_stack_t::get(const wcstring &key, env_mode_flags_t mode)
             wcstring_list_t result;
             if (history) history->get_history(result);
             return env_var_t(L"history", result);
+        } else if (key == L"pipestatus") {
+            const auto& js = proc_get_last_job_statuses();
+            wcstring_list_t result;
+            result.reserve(js->size());
+            for (auto&& i : *js) {
+                result.emplace_back(to_string(i));
+            }
+            return env_var_t(L"pipestatus", result);
         } else if (key == L"status") {
             return env_var_t(L"status", to_string(proc_get_last_status()));
         } else if (key == L"umask") {

src/event.cpp

@@ -275,6 +275,7 @@ static void event_fire_internal(const event_t &event) {
         // non-interactive.
         proc_push_interactive(0);
         int prev_status = proc_get_last_status();
+        const auto& saved_job_statuses = proc_get_last_job_statuses();
         parser_t &parser = parser_t::principal_parser();
 
         event_block_t *b = parser.push_block<event_block_t>(event);
@@ -282,6 +283,7 @@ static void event_fire_internal(const event_t &event) {
         parser.pop_block(b);
         proc_pop_interactive();
         proc_set_last_status(prev_status);
+        proc_set_last_job_statuses(std::move(saved_job_statuses));
     }
 }
 

src/exec.cpp

@@ -824,6 +824,7 @@ static bool exec_block_or_func_process(parser_t &parser, std::shared_ptr<job_t>
     }
 
     int status = proc_get_last_status();
+    p->status = status;
 
     // If we have a block output buffer, populate it now.
     if (!block_output_bufferfill) {
@@ -1056,6 +1057,7 @@ bool exec_job(parser_t &parser, shared_ptr<job_t> j) {
     }
 
     j->continue_job(false);
+    proc_set_last_job_statuses(*j);
     return true;
 }
 
@@ -1064,6 +1066,7 @@ static int exec_subshell_internal(const wcstring &cmd, parser_t &parser, wcstrin
     ASSERT_IS_MAIN_THREAD();
     bool prev_subshell = is_subshell;
     const int prev_status = proc_get_last_status();
+    const auto& prev_job_statuses = proc_get_last_job_statuses();
     bool split_output = false;
 
     const auto ifs = parser.vars().get(L"IFS");
@@ -1090,7 +1093,14 @@ static int exec_subshell_internal(const wcstring &cmd, parser_t &parser, wcstrin
 
     // If the caller asked us to preserve the exit status, restore the old status. Otherwise set the
     // status of the subcommand.
-    proc_set_last_status(apply_exit_status ? subcommand_status : prev_status);
+    if (apply_exit_status) {
+        proc_set_last_status(subcommand_status);
+    }
+    else {
+        proc_set_last_job_statuses(std::move(prev_job_statuses));
+        proc_set_last_status(prev_status);
+    }
+
     is_subshell = prev_subshell;
 
     if (lst == NULL || !buffer) {

src/input.cpp

@@ -367,10 +367,12 @@ static void input_mapping_execute(const input_mapping_t &m, bool allow_commands)
         // FIXME(snnw): if commands add stuff to input queue (e.g. commandline -f execute), we won't
         // see that until all other commands have also been run.
         int last_status = proc_get_last_status();
+        const auto& last_job_statuses = proc_get_last_job_statuses();
         for (const wcstring &cmd : m.commands) {
             parser_t::principal_parser().eval(cmd, io_chain_t(), TOP);
         }
         proc_set_last_status(last_status);
+        proc_set_last_job_statuses(std::move(last_job_statuses));
         input_common_next_ch(R_NULL);
     } else {
         // Invalid binding, mixed commands and functions.  We would need to execute these one by

src/parse_execution.cpp

@@ -718,6 +718,7 @@ parse_execution_result_t parse_execution_context_t::handle_command_not_found(
 
     // Set the last proc status appropriately.
     proc_set_last_status(err_code == ENOENT ? STATUS_CMD_UNKNOWN : STATUS_NOT_EXECUTABLE);
+    proc_set_last_job_statuses(proc_get_last_status());
 
     return parse_execution_errored;
 }

src/proc.cpp

@@ -53,6 +53,9 @@
 /// Status of last process to exit.
 static int last_status = 0;
 
+/// Statuses of last job's processes to exit - ensure we start off with one entry of 0.
+static std::shared_ptr<std::vector<int>> last_job_statuses = std::make_shared<std::vector<int>>(1);
+
 /// The signals that signify crashes to us.
 static const int crashsignals[] = {SIGABRT, SIGBUS, SIGFPE, SIGILL, SIGSEGV, SIGSYS};
 
@@ -139,6 +142,33 @@ void proc_set_last_status(int s) {
 
 int proc_get_last_status() { return last_status; }
 
+void proc_set_last_job_statuses(const job_t &last_job) {
+    ASSERT_IS_MAIN_THREAD();
+    auto ljs = std::make_shared<std::vector<int>>();
+    ljs->reserve(last_job.processes.size());
+    for (auto &&p : last_job.processes) {
+        ljs->emplace_back(p->pid ? proc_format_status(p->status) : p->status);
+    }
+    last_job_statuses = std::move(ljs);
+}
+
+void proc_set_last_job_statuses(std::shared_ptr<std::vector<int>> job_statuses) {
+    ASSERT_IS_MAIN_THREAD();
+    last_job_statuses = std::move(job_statuses);
+}
+
+void proc_set_last_job_statuses(const int job_status) {
+    ASSERT_IS_MAIN_THREAD();
+    auto ljs = std::make_shared<std::vector<int>>(1);
+    (*ljs)[0] = job_status;
+    last_job_statuses = std::move(ljs);
+}
+
+std::shared_ptr<std::vector<int>> proc_get_last_job_statuses() {
+    ASSERT_IS_MAIN_THREAD();
+    return last_job_statuses;
+}
+
 // Basic thread safe job IDs. The vector consumed_job_ids has a true value wherever the job ID
 // corresponding to that slot is in use. The job ID corresponding to slot 0 is 1.
 static owning_lock<std::vector<bool>> locked_consumed_job_ids;

src/proc.h

@@ -416,6 +416,14 @@ void proc_set_last_status(int s);
 /// Returns the status of the last process to exit.
 int proc_get_last_status();
 
+/// Sets the status of the last job's processes to exit from last_job.
+void proc_set_last_job_statuses(const job_t &last_job);
+void proc_set_last_job_statuses(std::shared_ptr<std::vector<int>>);
+void proc_set_last_job_statuses(const int); // for errors where pipe is unknown
+
+/// Returns the status of the last job's processes to exit.
+std::shared_ptr<std::vector<int>> proc_get_last_job_statuses();
+
 /// Notify the user about stopped or terminated jobs. Delete terminated jobs from the job list.
 ///
 /// \param interactive whether interactive jobs should be reaped as well

tests/pipestatus.err

@@ -0,0 +1,18 @@
+
+####################
+# pipestatus variable - builtins only
+
+####################
+# pipestatus variable - no builtins
+
+####################
+# pipestatus variable - mixed
+
+####################
+# pipestatus variable - non-pipe
+
+####################
+# pipestatus variable - negate
+
+####################
+# pipestatus variable - block

tests/pipestatus.expect

@@ -0,0 +1,79 @@
+# vim: set filetype=expect:
+#
+# Verify `$pipestatus` is preserved to next prompt.
+
+spawn $fish
+
+expect_prompt
+
+# no pipe
+send_line "true"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "0 : 0" {}
+send_line "false"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "1 : 1" {}
+
+# no pipe but negated
+send_line "! true"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "0 : 1" {}
+send_line "! false"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "1 : 0" {}
+
+# pipe
+send_line "false | true | false"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "1 0 1 : 1" {}
+
+# pipe negated
+send_line "! false | true | false"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "1 0 1 : 0" {}
+
+# pipe mixed with builtins and external
+send_line "command true | false | true | true"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "0 1 0 0 : 0" {}
+send_line "command true | command false | command false"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "0 1 1 : 1" {}
+send_line "sh -c 'exit 3' | command false | sh -c 'exit 5'"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "3 1 5 : 5" {}
+
+# negated pipe with mixed builtin and external
+send_line "! sh -c 'exit 3' | command false | sh -c 'exit 5'"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "3 1 5 : 0" {}
+
+# block
+send_line "command false | begin; command true; end | true"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "1 0 0 : 0" {}
+send_line "command false | begin; ! true; end | true"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "1 1 0 : 0" {}
+
+# syntax error
+send_line "syntax terror"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "127 : 127" {}
+send_line "syntax | terror"
+expect_prompt
+send_line "echo \$pipestatus : \$status"
+expect_prompt "127 : 127" {}

tests/pipestatus.in

@@ -0,0 +1,59 @@
+logmsg "pipestatus variable - builtins only"
+
+false | false | false; echo $pipestatus : $status
+true | true | true; echo $pipestatus : $status
+false | true | false; echo $pipestatus : $status
+true | false | true; echo $pipestatus : $status
+
+logmsg "pipestatus variable - no builtins"
+
+command false | command false | command false; echo $pipestatus : $status
+command true | command true | command true; echo $pipestatus : $status
+command false | command true | command false; echo $pipestatus : $status
+command true | command false | command true; echo $pipestatus : $status
+
+logmsg "pipestatus variable - mixed"
+
+command false | command false | false; echo $pipestatus : $status
+command true | true | command true; echo $pipestatus : $status
+false | command true | command false; echo $pipestatus : $status
+true | false | command true; echo $pipestatus : $status
+sh -c 'exit 5' | sh -c 'exit 2'; echo $pipestatus : $status
+sh -c 'exit 3' | false | sh -c 'exit 6'; echo $pipestatus : $status
+sh -c 'exit 9' | true | sh -c 'exit 3' | false; echo $pipestatus : $status
+
+logmsg "pipestatus variable - non-pipe"
+
+true; echo $pipestatus : $status
+false; echo $pipestatus : $status
+command true; echo $pipestatus : $status
+command false; echo $pipestatus : $status
+sh -c 'exit 4'; echo $pipestatus : $status
+
+logmsg "pipestatus variable - negate"
+
+! true; echo $pipestatus : $status
+! false; echo $pipestatus : $status
+! false | false | false; echo $pipestatus : $status
+! true | command true | true; echo $pipestatus : $status
+! false | true | command false; echo $pipestatus : $status
+! command true | command false | command true; echo $pipestatus : $status
+! sh -c 'exit 9' | true | sh -c 'exit 3'; echo $pipestatus : $status
+
+logmsg "pipestatus variable - block"
+
+begin; true; end; echo $pipestatus : $status
+begin; false; end; echo $pipestatus : $status
+begin; ! true; end; echo $pipestatus : $status
+begin; ! false; end; echo $pipestatus : $status
+true | begin; true; end; echo $pipestatus : $status
+false | begin; false; end; echo $pipestatus : $status
+true | begin; ! true; end; echo $pipestatus : $status
+false | begin; ! false; end; echo $pipestatus : $status
+begin; true | false; end; echo $pipestatus : $status
+begin; false | true; end; echo $pipestatus : $status
+begin; ! true; end | false ; echo $pipestatus : $status
+begin; ! false; end | true; echo $pipestatus : $status
+begin; sh -c 'exit 3'; end | begin; sh -c 'exit 5'; end; echo $pipestatus : $status
+begin; ! sh -c 'exit 3'; end | begin; sh -c 'exit 5'; end; echo $pipestatus : $status
+begin; ! sh -c 'exit 3'; end | begin; ! sh -c 'exit 5'; end; echo $pipestatus : $status

tests/pipestatus.out

@@ -0,0 +1,60 @@
+
+####################
+# pipestatus variable - builtins only
+1 1 1 : 1
+0 0 0 : 0
+1 0 1 : 1
+0 1 0 : 0
+
+####################
+# pipestatus variable - no builtins
+1 1 1 : 1
+0 0 0 : 0
+1 0 1 : 1
+0 1 0 : 0
+
+####################
+# pipestatus variable - mixed
+1 1 1 : 1
+0 0 0 : 0
+1 0 1 : 1
+0 1 0 : 0
+5 2 : 2
+3 1 6 : 6
+9 0 3 1 : 1
+
+####################
+# pipestatus variable - non-pipe
+0 : 0
+1 : 1
+0 : 0
+1 : 1
+4 : 4
+
+####################
+# pipestatus variable - negate
+0 : 1
+1 : 0
+1 1 1 : 0
+0 0 0 : 1
+1 0 1 : 0
+0 1 0 : 1
+9 0 3 : 0
+
+####################
+# pipestatus variable - block
+0 : 0
+1 : 1
+0 : 1
+1 : 0
+0 0 : 0
+1 1 : 1
+0 1 : 1
+1 0 : 0
+0 1 : 1
+1 0 : 0
+1 1 : 1
+0 0 : 0
+3 5 : 5
+0 5 : 5
+0 0 : 0