Try to obtain real email from environment, VCS in bdep-new

4 files changed, 158 insertions, 2 deletions

diff --git a/bdep/new.cli b/bdep/new.cli
index e700985..df77717 100644
--- a/bdep/new.cli
+++ b/bdep/new.cli
@@ -245,4 +245,13 @@ namespace bdep
        working directory."
     }
   };
+
+  "\h|ENVIRONMENT|
+
+   The \cb{BDEP_EMAIL} environment variable can be used to specify the package
+   email address. If not set, the \cb{new} command will first try to obtain
+   the email from the version control system (if used) and then from the
+   \cb{EMAIL} environment variable. If all these methods fail, a dummy
+   \cb{@example.org} email is used.
+  "
 }
diff --git a/bdep/new.cxx b/bdep/new.cxx
index ab8b255..9869fe7 100644
--- a/bdep/new.cxx
+++ b/bdep/new.cxx
@@ -5,6 +5,7 @@
 #include <bdep/new.hxx>
 
 #include <bdep/project.hxx>
+#include <bdep/project-email.hxx>
 #include <bdep/database.hxx>
 #include <bdep/diagnostics.hxx>
 
@@ -172,7 +173,8 @@ namespace bdep
       fail << "directory " << out << " already exists";
 
     // Initialize the version control system. Do it before writing anything
-    // ourselves in case it fails.
+    // ourselves in case it fails. Also, the email discovery may do the VCS
+    // detection.
     //
     if (!pkg)
     {
@@ -257,6 +259,12 @@ namespace bdep
 
       // manifest
       //
+      string email;
+      {
+        optional<string> r (project_email (prj));
+        email = r ? move (*r) : "you@example.org";
+      }
+
       os.open (f = out / "manifest");
       os << ": 1"                                                      << endl
          << "name: " << n                                              << endl
@@ -264,7 +272,7 @@ namespace bdep
          << "summary: " << s << " " << t                               << endl
          << "license: TODO"                                            << endl
          << "url: https://example.org/" << n                           << endl
-         << "email: you@example.org"                                   << endl
+         << "email: " << email                                         << endl
          << "depends: * build2 >= 0.8.0-"                              << endl
          << "depends: * bpkg >= 0.8.0-"                                << endl
          << "#depends: libhello ^1.0.0"                                << endl;
diff --git a/bdep/project-email.cxx b/bdep/project-email.cxx
new file mode 100644
index 0000000..20279a0
--- /dev/null
+++ b/bdep/project-email.cxx
@@ -0,0 +1,116 @@
+// file      : bdep/project-email.cxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2018 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#include <bdep/project-email.hxx>
+
+#include <libbutl/filesystem.mxx>
+
+#include <bdep/diagnostics.hxx>
+
+using namespace butl;
+
+namespace bdep
+{
+  optional<string>
+  project_email (const dir_path& prj)
+  {
+    optional<string> r;
+
+    // The search order is as follows:
+    //
+    // BDEP_EMAIL
+    // <VCS>
+    // EMAIL
+    //
+    if ((r = getenv ("BDEP_EMAIL")))
+      return r;
+
+    // See if this is a VCS repository we recognize.
+    //
+
+    // .git can be either a directory or a file in case of a submodule.
+    //
+    if (entry_exists (prj / ".git",
+                      true /* follow_symlinks */,
+                      true /* ignore_errors */))
+    {
+      // In git the author email can be specified with the GIT_AUTHOR_EMAIL
+      // environment variable after which things fall back to the committer
+      // (GIT_COMMITTER_EMAIL and then the user.email git-config value). The
+      // resolved value can be queried with the GIT_AUTHOR_IDENT logical
+      // variable.
+      //
+      process pr;
+      bool io (false);
+      try
+      {
+        fdpipe pipe (fdopen_pipe ());
+
+        // If git cannot determine the author name/email, it fails verbosely
+        // so we suppress all diagnostics.
+        //
+        pr = start (0         /* stdin  */,
+                    pipe      /* stdout */,
+                    fdnull () /* stderr */,
+                    "git",
+                    "-C", prj,
+                    "var",
+                    "GIT_AUTHOR_IDENT");
+
+        pipe.out.close ();
+        ifdstream is (move (pipe.in), ifdstream::badbit);
+
+        // The output should be a single line in this form:
+        //
+        // NAME <EMAIL> TIME ZONE
+        //
+        // For example:
+        //
+        // John Doe <john@example.org> 1530517726 +0200
+        //
+        // The <> delimiters are there even if the email is empty so we use
+        // them as anchors.
+        //
+        string l;
+        if (!eof (getline (is, l)))
+        {
+          size_t p1, p2;
+
+          if ((p2 = l.rfind ('>'    )) == string::npos ||
+              (p1 = l.rfind ('<', p2)) == string::npos)
+            fail << "no email in git-var output";
+
+          if (++p1 != p2)
+            r = string (l, p1, p2 - p1);
+        }
+
+        is.close (); // Detect errors.
+      }
+      catch (const io_error&)
+      {
+        io = true; // Presumably git failed so check that first.
+      }
+
+      if (!pr.wait ())
+      {
+        const process_exit& e (*pr.exit);
+
+        if (!e.normal ())
+          fail << "process git " << e;
+
+        r = nullopt;
+      }
+      else if (io)
+        fail << "unable to read git-var output";
+
+      if (r)
+        return r;
+    }
+
+    if ((r = getenv ("EMAIL")))
+      return r;
+
+    return r;
+  }
+}
diff --git a/bdep/project-email.hxx b/bdep/project-email.hxx
new file mode 100644
index 0000000..c630682
--- /dev/null
+++ b/bdep/project-email.hxx
@@ -0,0 +1,23 @@
+// file      : bdep/project-email.hxx -*- C++ -*-
+// copyright : Copyright (c) 2014-2018 Code Synthesis Ltd
+// license   : MIT; see accompanying LICENSE file
+
+#ifndef BDEP_PROJECT_EMAIL_HXX
+#define BDEP_PROJECT_EMAIL_HXX
+
+#include <bdep/types.hxx>
+#include <bdep/utility.hxx>
+
+namespace bdep
+{
+  // Given a project directly, try to discover the author's email address
+  // using the environment and, if project looks like a repository, its VCS.
+  //
+  // Note: if using this function in a command, don't forget to update its
+  // ENVIRONMENT section to mention BDEP_EMAIL.
+  //
+  optional<string>
+  project_email (const dir_path&);
+}
+
+#endif // BDEP_PROJECT_EMAIL_HXX