eval: Implement jobclose() vimscript function

runtime/doc/eval.txt

@@ -4012,6 +4012,10 @@ items({dict})						*items()*
 		entry and the value of this entry.  The |List| is in arbitrary
 		order.
 
+jobclose({job}[, {stream}])				{Nvim} *jobclose()*
+		Close {job}'s {stream}, which can be one "stdin", "stdout" or
+		"stderr". If {stream} is omitted, all streams are closed.
+
 jobresize({job}, {width}, {height})			{Nvim} *jobresize()*
 		Resize {job}'s pseudo terminal window to {width} and {height}.
 		This function will fail if used on jobs started without the

src/nvim/eval.c

@@ -445,6 +445,7 @@ typedef struct {
   Job *job;
   Terminal *term;
   bool exited;
+  bool stdin_closed;
   int refcount;
   ufunc_T *on_stdout, *on_stderr, *on_exit;
   dict_T *self;
@@ -6535,6 +6536,7 @@ static struct fst {
   {"isdirectory",     1, 1, f_isdirectory},
   {"islocked",        1, 1, f_islocked},
   {"items",           1, 1, f_items},
+  {"jobclose",        1, 2, f_jobclose},
   {"jobresize",       3, 3, f_jobresize},
   {"jobsend",         2, 2, f_jobsend},
   {"jobstart",        1, 2, f_jobstart},
@@ -10658,6 +10660,48 @@ static void f_items(typval_T *argvars, typval_T *rettv)
   dict_list(argvars, rettv, 2);
 }
 
+// "jobclose(id[, stream])" function
+static void f_jobclose(typval_T *argvars, typval_T *rettv)
+{
+  rettv->v_type = VAR_NUMBER;
+  rettv->vval.v_number = 0;
+
+  if (check_restricted() || check_secure()) {
+    return;
+  }
+
+  if (argvars[0].v_type != VAR_NUMBER || (argvars[1].v_type != VAR_STRING
+        && argvars[1].v_type != VAR_UNKNOWN)) {
+    EMSG(_(e_invarg));
+    return;
+  }
+
+  Job *job = job_find(argvars[0].vval.v_number);
+
+  if (!is_user_job(job)) {
+    // Invalid job id
+    EMSG(_(e_invjob));
+    return;
+  }
+
+  if (argvars[1].v_type == VAR_STRING) {
+    char *stream = (char *)argvars[1].vval.v_string;
+    if (!strcmp(stream, "stdin")) {
+      job_close_in(job);
+      ((TerminalJobData *)job_data(job))->stdin_closed = true;
+    } else if (!strcmp(stream, "stdout")) {
+      job_close_out(job);
+    } else if (!strcmp(stream, "stderr")) {
+      job_close_err(job);
+    } else {
+      EMSG2(_("Invalid job stream \"%s\""), stream);
+    }
+  } else {
+    ((TerminalJobData *)job_data(job))->stdin_closed = true;
+    job_close_streams(job);
+  }
+}
+
 // "jobsend()" function
 static void f_jobsend(typval_T *argvars, typval_T *rettv)
 {
@@ -10683,6 +10727,11 @@ static void f_jobsend(typval_T *argvars, typval_T *rettv)
     return;
   }
 
+  if (((TerminalJobData *)job_data(job))->stdin_closed) {
+    EMSG(_("Can't send data to the job: stdin is closed"));
+    return;
+  }
+
   ssize_t input_len;
   char *input = (char *) save_tv_as_string(&argvars[1], &input_len, false);
   if (!input) {

src/nvim/os/job.c

@@ -290,6 +290,18 @@ void job_close_in(Job *job) FUNC_ATTR_NONNULL_ALL
   close_job_in(job);
 }
 
+// Close the job stdout stream.
+void job_close_out(Job *job) FUNC_ATTR_NONNULL_ALL
+{
+  close_job_out(job);
+}
+
+// Close the job stderr stream.
+void job_close_err(Job *job) FUNC_ATTR_NONNULL_ALL
+{
+  close_job_out(job);
+}
+
 /// All writes that complete after calling this function will be reported
 /// to `cb`.
 ///

test/functional/job/job_spec.lua

@@ -107,6 +107,20 @@ describe('jobs', function()
     eq({'notification', 'exit', {0, 0}}, next_msg())
   end)
 
+  it('can close the job streams with jobclose', function()
+    nvim('command', "let j = jobstart(['cat', '-'], g:job_opts)")
+    nvim('command', 'call jobclose(j, "stdin")')
+    eq({'notification', 'exit', {0, 0}}, next_msg())
+  end)
+
+  it('wont allow jobsend with a job that closed stdin', function()
+    nvim('command', "let j = jobstart(['cat', '-'], g:job_opts)")
+    nvim('command', 'call jobclose(j, "stdin")')
+    eq(false, pcall(function()
+      nvim('command', 'call jobsend(j, ["some data"])')
+    end))
+  end)
+
   it('will not allow jobsend/stop on a non-existent job', function()
     eq(false, pcall(eval, "jobsend(-1, 'lol')"))
     eq(false, pcall(eval, "jobstop(-1)"))