installer: Support showing status information in terminal title (#16259)

Installing packages with a lot of dependencies does not have an easy way
of judging the current progress (apart from running `spack spec -I pkg`
in another terminal). This change allows Spack to update the terminal's
title with status information, including its current progress as well as
information about the current and total number of packages.

4 files changed, 49 insertions, 2 deletions

diff --git a/etc/spack/defaults/config.yaml b/etc/spack/defaults/config.yaml
index 88a19d3222..3487d33162 100644
--- a/etc/spack/defaults/config.yaml
+++ b/etc/spack/defaults/config.yaml
@@ -134,7 +134,7 @@ config:
   # enabling locks.
   locks: true
 
-  # The default url fetch method to use. 
+  # The default url fetch method to use.
   # If set to 'curl', Spack will require curl on the user's system
   # If set to 'urllib', Spack will use python built-in libs to fetch
   url_fetch_method: urllib
@@ -190,3 +190,8 @@ config:
   # Set to 'false' to allow installation on filesystems that doesn't allow setgid bit
   # manipulation by unprivileged user (e.g. AFS)
   allow_sgid: true
+
+  # Whether to set the terminal title to display status information during
+  # building and installing packages. This gives information about Spack's
+  # current progress as well as the current and total number of packages.
+  terminal_title: false
diff --git a/lib/spack/docs/config_yaml.rst b/lib/spack/docs/config_yaml.rst
index 631b8f6b1b..8173e8a0a9 100644
--- a/lib/spack/docs/config_yaml.rst
+++ b/lib/spack/docs/config_yaml.rst
@@ -259,3 +259,16 @@ and ld.so will ONLY search for dependencies in the ``RUNPATH`` of
 the loading object.
 
 DO NOT MIX the two options within the same install tree.
+
+----------------------
+``terminal_title``
+----------------------
+
+By setting this option to ``true``, Spack will update the terminal's title to
+provide information about its current progress as well as the current and
+total package numbers.
+
+To work properly, this requires your terminal to reset its title after
+Spack has finished its work, otherwise Spack's status information will
+remain in the terminal's title indefinitely. Most terminals should already
+be set up this way and clear Spack's status information.
diff --git a/lib/spack/llnl/util/tty/log.py b/lib/spack/llnl/util/tty/log.py
index bc79b32335..7003f58f8d 100644
--- a/lib/spack/llnl/util/tty/log.py
+++ b/lib/spack/llnl/util/tty/log.py
@@ -33,7 +33,7 @@ except ImportError:
 
 
 # Use this to strip escape sequences
-_escape = re.compile(r'\x1b[^m]*m|\x1b\[?1034h')
+_escape = re.compile(r'\x1b[^m]*m|\x1b\[?1034h|\x1b\][0-9]+;[^\x07]*\x07')
 
 # control characters for enabling/disabling echo
 #
diff --git a/lib/spack/spack/installer.py b/lib/spack/spack/installer.py
index 11430bfc94..d7a6ca0a67 100644
--- a/lib/spack/spack/installer.py
+++ b/lib/spack/spack/installer.py
@@ -627,6 +627,27 @@ def package_id(pkg):
     return "{0}-{1}-{2}".format(pkg.name, pkg.version, pkg.spec.dag_hash())
 
 
+class TermTitle(object):
+    def __init__(self, pkg_count):
+        # Counters used for showing status information in the terminal title
+        self.pkg_num = 0
+        self.pkg_count = pkg_count
+
+    def next_pkg(self):
+        self.pkg_num += 1
+
+    def set(self, text):
+        if not spack.config.get('config:terminal_title', False):
+            return
+
+        if not sys.stdout.isatty():
+            return
+
+        status = '{0} [{1}/{2}]'.format(text, self.pkg_num, self.pkg_count)
+        sys.stdout.write('\033]0;Spack: {0}\007'.format(status))
+        sys.stdout.flush()
+
+
 class PackageInstaller(object):
     '''
     Class for managing the install process for a Spack instance based on a
@@ -1476,7 +1497,11 @@ class PackageInstaller(object):
         failed_explicits = []
         exists_errors = []
 
+        term_title = TermTitle(len(self.build_pq))
+
         while self.build_pq:
+            term_title.next_pkg()
+
             task = self._pop_task()
             if task is None:
                 continue
@@ -1486,6 +1511,7 @@ class PackageInstaller(object):
             keep_prefix = install_args.get('keep_prefix')
 
             pkg, pkg_id, spec = task.pkg, task.pkg_id, task.pkg.spec
+            term_title.set('Processing {0}'.format(pkg.name))
             tty.verbose('Processing {0}: task={1}'.format(pkg_id, task))
             # Ensure that the current spec has NO uninstalled dependencies,
             # which is assumed to be reflected directly in its priority.
@@ -1541,6 +1567,7 @@ class PackageInstaller(object):
             # another process is likely (un)installing the spec or has
             # determined the spec has already been installed (though the
             # other process may be hung).
+            term_title.set('Acquiring lock for {0}'.format(pkg.name))
             ltype, lock = self._ensure_locked('write', pkg)
             if lock is None:
                 # Attempt to get a read lock instead.  If this fails then
@@ -1561,6 +1588,7 @@ class PackageInstaller(object):
                 task.request.overwrite_time = time.time()
 
             # Determine state of installation artifacts and adjust accordingly.
+            term_title.set('Preparing {0}'.format(pkg.name))
             self._prepare_for_install(task)
 
             # Flag an already installed package
@@ -1605,6 +1633,7 @@ class PackageInstaller(object):
 
             # Proceed with the installation since we have an exclusive write
             # lock on the package.
+            term_title.set('Installing {0}'.format(pkg.name))
             try:
                 action = self._install_action(task)