Add support for *-build-*email package manifest values and their overrides

4 files changed, 434 insertions, 44 deletions

diff --git a/libbpkg/manifest.cxx b/libbpkg/manifest.cxx
index aeb9b0e..559e1c3 100644
--- a/libbpkg/manifest.cxx
+++ b/libbpkg/manifest.cxx
@@ -3557,10 +3557,21 @@ namespace bpkg
       };
 
     // Return the package build configuration with the specified name, if
-    // already exists, or the newly created configuration otherwise.
-    //
-    auto build_conf = [&m] (string&& nm) -> build_package_config&
-    {
+    // already exists. If no configuration matches, then create one, if
+    // requested, and throw manifest_parsing otherwise. If the new
+    // configuration creation is not allowed, then the description for a
+    // potential manifest_parsing exception needs to also be specified.
+    //
+    auto build_conf = [&m, &bad_name] (string&& nm,
+                                       bool create = true,
+                                       const string& desc = "")
+      -> build_package_config&
+    {
+      // The error description must only be specified if the creation of the
+      // package build configuration is not allowed.
+      //
+      assert (desc.empty () == create);
+
       small_vector<build_package_config, 1>& cs (m.build_configs);
 
       auto i (find_if (cs.begin (), cs.end (),
@@ -3570,6 +3581,9 @@ namespace bpkg
       if (i != cs.end ())
         return *i;
 
+      if (!create)
+        bad_name (desc + ": no build package configuration '" + nm + '\'');
+
       // Add the new build configuration (arguments, builds, etc will come
       // later).
       //
@@ -3601,6 +3615,16 @@ namespace bpkg
     vector<name_value>   changes;
     optional<name_value> changes_type;
 
+    // It doesn't make sense for only emails to be specified for a package
+    // build configuration. Thus, we will cache the build configuration email
+    // manifest values to parse them later, after all other build
+    // configuration values are parsed, and to make sure that the build
+    // configurations they refer to are also specified.
+    //
+    vector<name_value> build_config_emails;
+    vector<name_value> build_config_warning_emails;
+    vector<name_value> build_config_error_emails;
+
     m.build_configs.emplace_back ("default");
 
     for (nv = next (); !nv.empty (); nv = next ())
@@ -4033,6 +4057,24 @@ namespace bpkg
         bc.constraints.push_back (
           parse_build_constraint (nv, true /* exclusion */, name));
       }
+      else if (n.size () > 12 &&
+               n.compare (n.size () - 12, 12, "-build-email") == 0)
+      {
+        n.resize (n.size () - 12);
+        build_config_emails.push_back (move (nv));
+      }
+      else if (n.size () > 20 &&
+               n.compare (n.size () - 20, 20, "-build-warning-email") == 0)
+      {
+        n.resize (n.size () - 20);
+        build_config_warning_emails.push_back (move (nv));
+      }
+      else if (n.size () > 18 &&
+               n.compare (n.size () - 18, 18, "-build-error-email") == 0)
+      {
+        n.resize (n.size () - 18);
+        build_config_error_emails.push_back (move (nv));
+      }
       // @@ TMP time to drop *-0.14.0?
       //
       else if (n == "tests"      || n == "tests-0.14.0"    ||
@@ -4387,6 +4429,59 @@ namespace bpkg
       }
     }
 
+    // Parse the build configuration emails.
+    //
+    // Note: the argument can only be one of the build_config_*emails
+    // variables (see above) to distinguish between the email kinds.
+    //
+    auto parse_build_config_emails = [&name,
+                                      &nv,
+                                      &build_config_emails,
+                                      &build_config_warning_emails,
+                                      &build_config_error_emails,
+                                      &build_conf,
+                                      &parse_email]
+                                     (vector<name_value>&& emails)
+    {
+      enum email_kind {build, warning, error};
+
+      email_kind ek (
+        &emails == &build_config_emails         ? email_kind::build   :
+        &emails == &build_config_warning_emails ? email_kind::warning :
+        email_kind::error);
+
+      // The argument can only be one of the build_config_*emails variables.
+      //
+      assert (ek != email_kind::error || &emails == &build_config_error_emails);
+
+      for (name_value& e: emails)
+      {
+        // Restore as bad_name() and bad_value() use its line/column.
+        //
+        nv = move (e);
+
+        build_package_config& bc (
+          build_conf (move (nv.name),
+                      false /* create */,
+                      "stray build notification email"));
+
+        parse_email (
+          nv,
+          (ek == email_kind::build   ? bc.email         :
+           ek == email_kind::warning ? bc.warning_email :
+           bc.error_email),
+          (ek == email_kind::build   ? "build configuration"         :
+           ek == email_kind::warning ? "build configuration warning" :
+           "build configuration error"),
+          name,
+          ek == email_kind::build /* empty */);
+      }
+    };
+
+    parse_build_config_emails (move (build_config_emails));
+    parse_build_config_emails (move (build_config_warning_emails));
+    parse_build_config_emails (move (build_config_error_emails));
+
     // Now, when the version manifest value is parsed, we can parse the
     // dependencies and complete their constraints, if requested.
     //
@@ -4712,14 +4807,22 @@ namespace bpkg
 
     // The first {build-*email} override value.
     //
-    const manifest_name_value* be (nullptr);
+    const manifest_name_value* cbe (nullptr);
+
+    // The first {*-build-*email} override value.
+    //
+    const manifest_name_value* pbe  (nullptr);
 
-    // List of indexes of the overridden build configurations together with
-    // flags which indicate if the *-builds override value was encountered for
-    // this configuration.
+    // List of indexes of the build configurations with the overridden build
+    // constraints together with flags which indicate if the *-builds override
+    // value was encountered for this configuration.
     //
     vector<pair<size_t, bool>> obcs;
 
+    // List of indexes of the build configurations with the overridden emails.
+    //
+    vector<size_t> obes;
+
     // Apply overrides.
     //
     for (const manifest_name_value& nv: nvs)
@@ -4768,7 +4871,8 @@ namespace bpkg
       // otherwise.
       //
       // The n argument specifies the length of the configuration name in
-      // *-build-config, *-builds, and *-build-{include,exclude} values.
+      // *-build-config, *-builds, *-build-{include,exclude}, and
+      // *-build-*email values.
       //
       auto build_conf =
         [&nv, &bad_name, &m] (size_t n, bool create) -> build_package_config&
@@ -4869,19 +4973,77 @@ namespace bpkg
         return r;
       };
 
-      // Reset the {build-*email} value group on the first call.
+      // Reset the {build-*email} value group on the first call but throw if
+      // any of the {*-build-*email} override values are already encountered.
       //
-      auto reset_build_emails = [&be, &nv, &m] ()
+      auto reset_build_emails = [&cbe, &pbe, &nv, &bad_name, &m] ()
       {
-        if (be == nullptr)
+        if (cbe == nullptr)
         {
+          if (pbe != nullptr)
+            bad_name ('\'' + nv.name + "' override specified together with '" +
+                      pbe->name + "' override");
+
           m.build_email = nullopt;
           m.build_warning_email = nullopt;
           m.build_error_email = nullopt;
-          be = &nv;
+          cbe = &nv;
         }
       };
 
+      // Return the reference to the package build configuration which matches
+      // the build config-specific emails group value override, if exists. If
+      // no configuration matches, then throw manifest_parsing, except for the
+      // validate-only mode in which case just add an empty configuration with
+      // this name and return the reference to it.
+      //
+      auto build_conf_email =
+        [&pbe, &cbe, &nv, &obes, &bad_name, &build_conf, &m, validate_only]
+        (size_t n) -> build_package_config&
+      {
+        const string& nm (nv.name);
+
+        // If this is the first build config override value, then save its
+        // address. But first verify that no common build emails group value
+        // overrides are applied yet and throw if that's not the case.
+        //
+        if (pbe == nullptr)
+        {
+          if (cbe != nullptr)
+            bad_name ('\'' + nm + "' override specified together with '" +
+                      cbe->name + "' override");
+
+          pbe = &nv;
+        }
+
+        small_vector<build_package_config, 1>& cs (m.build_configs);
+
+        // Find the build package configuration. If there is no such a
+        // configuration then throw, except for the validate-only mode in
+        // which case just add an empty configuration with this name.
+        //
+        // Note that we are using indexes rather then configuration addresses
+        // due to potential reallocations.
+        //
+        build_package_config& r (build_conf (n, validate_only));
+        size_t ci (&r - cs.data ());
+
+        // If this is the first encountered {*-build-*email} override for this
+        // build config, then clear this config' email members and add an
+        // entry to the overridden configs list.
+        //
+        if (find (obes.begin (), obes.end (), ci) == obes.end ())
+        {
+          r.email = nullopt;
+          r.warning_email = nullopt;
+          r.error_email = nullopt;
+
+          obes.push_back (ci);
+        }
+
+        return r;
+      };
+
       const string& n (nv.name);
 
       if (n == "builds")
@@ -4954,6 +5116,29 @@ namespace bpkg
         reset_build_emails ();
         m.build_error_email = parse_email (nv, "build error", name);
       }
+      else if (n.size () > 12 &&
+               n.compare (n.size () - 12, 12, "-build-email") == 0)
+      {
+        build_package_config& bc (build_conf_email (n.size () - 12));
+
+        bc.email = parse_email (
+          nv, "build configuration", name, true /* empty */);
+      }
+      else if (n.size () > 20 &&
+               n.compare (n.size () - 20, 20, "-build-warning-email") == 0)
+      {
+        build_package_config& bc (build_conf_email (n.size () - 20));
+
+        bc.warning_email = parse_email (
+          nv, "build configuration warning", name);
+      }
+      else if (n.size () > 18 &&
+               n.compare (n.size () - 18, 18, "-build-error-email") == 0)
+      {
+        build_package_config& bc (build_conf_email (n.size () - 18));
+
+        bc.error_email = parse_email (nv, "build configuration error", name);
+      }
       else
         bad_name ("cannot override '" + n + "' value");
     }
@@ -4964,8 +5149,8 @@ namespace bpkg
     assert (cbc == nullptr || pbc == nullptr);
 
     // Now, if not in the validate-only mode, as all the potential build
-    // constraint overrides are applied, perform the final adjustments to the
-    // build config constraints.
+    // constraint/email overrides are applied, perform the final adjustments
+    // to the build config constraints/emails.
     //
     if (!validate_only)
     {
@@ -4993,6 +5178,30 @@ namespace bpkg
           }
         }
       }
+
+      if (cbe != nullptr)      // Common build emails are overridden?
+      {
+        for (build_package_config& c: m.build_configs)
+        {
+          c.email = nullopt;
+          c.warning_email = nullopt;
+          c.error_email = nullopt;
+        }
+      }
+      else if (pbe != nullptr) // Build config emails are overridden?
+      {
+        for (size_t i (0); i != m.build_configs.size (); ++i)
+        {
+          if (find (obes.begin (), obes.end (), i) == obes.end ())
+          {
+            build_package_config& c (m.build_configs[i]);
+
+            c.email = email ();
+            c.warning_email = nullopt;
+            c.error_email = nullopt;
+          }
+        }
+      }
     }
   }
 
@@ -5303,10 +5512,6 @@ namespace bpkg
 
       for (const build_package_config& bc: m.build_configs)
       {
-        if (!bc.arguments.empty () || !bc.comment.empty ())
-          s.next (bc.name + "-build-config",
-                  serializer::merge_comment (bc.arguments, bc.comment));
-
         if (!bc.builds.empty ())
         {
           string n (bc.name + "-builds");
@@ -5326,6 +5531,24 @@ namespace bpkg
                                                : c.config + '/' + *c.target,
                                                c.comment));
         }
+
+        if (!bc.arguments.empty () || !bc.comment.empty ())
+          s.next (bc.name + "-build-config",
+                  serializer::merge_comment (bc.arguments, bc.comment));
+
+        if (bc.email)
+          s.next (bc.name + "-build-email",
+                  serializer::merge_comment (*bc.email, bc.email->comment));
+
+        if (bc.warning_email)
+          s.next (bc.name + "-build-warning-email",
+                  serializer::merge_comment (*bc.warning_email,
+                                             bc.warning_email->comment));
+
+        if (bc.error_email)
+          s.next (bc.name + "-build-error-email",
+                  serializer::merge_comment (*bc.error_email,
+                                             bc.error_email->comment));
       }
 
       bool an (m.alt_naming && *m.alt_naming);
diff --git a/libbpkg/manifest.hxx b/libbpkg/manifest.hxx
index dce0870..8439cdf 100644
--- a/libbpkg/manifest.hxx
+++ b/libbpkg/manifest.hxx
@@ -980,12 +980,15 @@ namespace bpkg
     return os << bce.string ();
   }
 
-  // Package build configuration. Includes comment and optional target build
-  // configuration class expressions/constraints overrides.
+  // Package build configuration. Includes comment and optional overrides for
+  // target build configuration class expressions/constraints and build
+  // notification emails.
   //
   class build_package_config
   {
   public:
+    using email_type = bpkg::email;
+
     std::string name;
 
     // Whitespace separated list of potentially double/single-quoted package
@@ -999,6 +1002,10 @@ namespace bpkg
     butl::small_vector<build_class_expr, 1> builds;
     std::vector<build_constraint> constraints;
 
+    butl::optional<email_type> email;
+    butl::optional<email_type> warning_email;
+    butl::optional<email_type> error_email;
+
     build_package_config () = default;
 
     // Built incrementally.
@@ -1024,6 +1031,31 @@ namespace bpkg
     {
       return !builds.empty () || !constraints.empty () ? constraints : common;
     }
+
+    // Return the configuration's build notification emails if they override
+    // the specified common build notification emails and return the latter
+    // otherwise (see package_manifest::override() for the override semantics
+    // details).
+    //
+    const butl::optional<email_type>&
+    effective_email (const butl::optional<email_type>& common) const noexcept
+    {
+      return email || warning_email || error_email ? email : common;
+    }
+
+    const butl::optional<email_type>&
+    effective_warning_email (const butl::optional<email_type>& common) const
+      noexcept
+    {
+      return email || warning_email || error_email ? warning_email : common;
+    }
+
+    const butl::optional<email_type>&
+    effective_error_email (const butl::optional<email_type>& common) const
+      noexcept
+    {
+      return email || warning_email || error_email ? error_email : common;
+    }
   };
 
   enum class test_dependency_type
@@ -1330,14 +1362,15 @@ namespace bpkg
     //   {builds, build-{include,exclude}}
     //   {*-builds, *-build-{include,exclude}}
     //   {*-build-config}
+    //   {*-build-*email}
     //
     // Throw manifest_parsing if the configuration specified by the build
-    // package configuration-specific build constraints group value overrides
-    // doesn't exists. In contrast, for the build config override add a new
-    // configuration if it doesn't exist and update the arguments of the
-    // existing configuration otherwise. In the former case, all the potential
-    // build constraints overrides for such a newly added configuration must
-    // follow the respective *-build-config override.
+    // package configuration-specific build constraints or emails group value
+    // overrides doesn't exists. In contrast, for the build config override
+    // add a new configuration if it doesn't exist and update the arguments of
+    // the existing configuration otherwise. In the former case, all the
+    // potential build constraints and emails overrides for such a newly added
+    // configuration must follow the respective *-build-config override.
     //
     // Note that the build constraints group values (both common and build
     // config-specific) are overridden hierarchically so that the
@@ -1351,6 +1384,15 @@ namespace bpkg
     // constraints are overridden, then for the remaining configs the build
     // constraints are reset to `builds: none`.
     //
+    // Similar to the build constraints groups, the common and build
+    // config-specific build emails group value overrides are mutually
+    // exclusive. If the common build emails are overridden, then all the
+    // build config-specific emails are reset to nullopt. Otherwise, if some
+    // build config-specific emails are overridden, then for the remaining
+    // configs the email is reset to the empty value and the warning and error
+    // emails are reset to nullopt (which effectively disables email
+    // notifications for such configurations).
+    //
     // If a non-empty source name is specified, then the specified values are
     // assumed to also include the line/column information and the possibly
     // thrown manifest_parsing exception will contain the invalid value's
diff --git a/tests/manifest/testscript b/tests/manifest/testscript
index 7d808e3..3179005 100644
--- a/tests/manifest/testscript
+++ b/tests/manifest/testscript
@@ -1060,8 +1060,8 @@
         version: 2.0.0
         summary: Modern C++ parser
         license: LGPLv2
-        bar-build-config: config.foo.bar = true; Bar.
         bar-builds: all
+        bar-build-config: config.foo.bar = true; Bar.
         baz-build-config: config.foo.baz = true; Baz.
         EOF
     }
@@ -1111,6 +1111,81 @@
         bar-builds: all
         EOI
     }
+
+    : email
+    :
+    {
+      : override
+      :
+      {
+        $* <<EOF >>EOF
+          : 1
+          name: foo
+          version: 2.0.0
+          summary: Modern C++ parser
+          license: LGPLv2
+          package-email: package@example.com
+          build-email: build@example.com
+          build-warning-email: build-warning@example.com
+          build-error-email: build-error@example.com
+          bar-build-config: config.foo.bar = true; Bar.
+          bar-build-email: bar-build@example.com
+          bar-build-warning-email: bar-build-warning@example.com
+          bar-build-error-email: bar-build-error@example.com
+          EOF
+      }
+
+      : disabled
+      :
+      {
+        $* <<EOF >>EOF
+          : 1
+          name: foo
+          version: 2.0.0
+          summary: Modern C++ parser
+          license: LGPLv2
+          package-email: package@example.com
+          build-email: build@example.com
+          build-warning-email: build-warning@example.com
+          build-error-email: build-error@example.com
+          bar-build-config: config.foo.bar = true; Bar.
+          bar-build-email:
+          EOF
+      }
+
+      : unrecognized
+      :
+      {
+        $* <<EOI 2>>EOE != 0
+          : 1
+          name: foo
+          version: 2.0.0
+          summary: Modern C++ parser
+          license: LGPLv2
+          build-error-email: build-error@example.com
+          bar-build-email: bar-build@example.com
+          EOI
+          stdin:7:1: error: stray build notification email: no build package configuration 'bar'
+          EOE
+      }
+
+      : empty
+      :
+      {
+        $* <<EOI 2>>EOE != 0
+          : 1
+          name: foo
+          version: 2.0.0
+          summary: Modern C++ parser
+          license: LGPLv2
+          build-error-email: build-error@example.com
+          bar-build-config: config.foo.bar = true; Bar.
+          bar-build-warning-email: ; Empty
+          EOI
+          stdin:8:26: error: empty build configuration warning email
+          EOE
+      }
+    }
   }
 
   : distribution
@@ -4447,10 +4522,10 @@
       build-include: linux*
       build-include: freebsd*
       build-exclude: *; Only supports Linux and FreeBSD.
-      network-build-config: config.libfoo.network=true; Enable networking API.
       network-builds: default
       network-build-include: linux*
       network-build-exclude: *; Only supports Linux.
+      network-build-config: config.libfoo.network=true; Enable networking API.
       bootstrap-build:\
       project = libfoo
 
diff --git a/tests/overrides/testscript b/tests/overrides/testscript
index 07c1451..ba66b7f 100644
--- a/tests/overrides/testscript
+++ b/tests/overrides/testscript
@@ -15,6 +15,10 @@
     build-email: foo@example.com
     build-error-email: error@example.com
     build-warning-email: warning@example.com
+    network-build-config: config.libfoo.network=true
+    network-build-email: network-foo@example.com
+    network-build-error-email: network-error@example.com
+    network-build-warning-email: network-warning@example.com
     EOI
     : 1
     name: libfoo
@@ -22,6 +26,7 @@
     summary: Modern C++ parser
     license: LGPLv2
     build-email: bar@example.com
+    network-build-config: config.libfoo.network=true
     EOO
 
   : builds
@@ -99,6 +104,8 @@
   : build-configs
   :
   $* 'network-builds: all' 'network-build-include: windows*' 'network-build-exclude: *' \
+     'network-build-warning-email: network-warning@example.com' 'sys-build-email:' \
+     'cache-build-error-email: cache-error@example.com' \
      'cache-build-include: freebsd*' 'cache-build-exclude: *' 'cache-builds: legacy' \
        'cache-build-config: config.libfoo.cache=true config.libfoo.buffer=1028' \
      'deprecated-api-build-config: config.libfoo.deprecated_api=true' 'deprecated-api-builds: windows' \
@@ -110,63 +117,80 @@
     version: 2.0.0
     summary: Modern C++ parser
     license: LGPLv2
+    build-email: foo@example.com
+    build-error-email: error@example.com
+    build-warning-email: warning@example.com
     builds: all
     build-include: linux*
     build-include: macos*
     build-include: freebsd*
     build-exclude: *
-    network-build-config: config.libfoo.network=true
     network-builds: default
     network-build-include: linux*
     network-build-exclude: *
-    cache-build-config: config.libfoo.cache=true
+    network-build-config: config.libfoo.network=true
+    network-build-error-email: network-error@example.com
     cache-builds: default
     cache-build-include: macos*
     cache-build-exclude: *
-    sys-build-config: ?sys:libcrypto
+    cache-build-config: config.libfoo.cache=true
+    cache-build-email: cache@example.com
     sys-builds: default
     sys-build-include: freebsd*
     sys-build-exclude: *
-    older-build-config: ?libbar/1.0.0
+    sys-build-config: ?sys:libcrypto
+    sys-build-email: sys@example.com
     older-builds: default
     older-build-include: windows*
     older-build-exclude: *
-    fancy-build-config: config.libfoo.fancy=true
+    older-build-config: ?libbar/1.0.0
     fancy-builds: default
     fancy-build-include: windows*
     fancy-build-exclude: *
+    fancy-build-config: config.libfoo.fancy=true
     EOI
     : 1
     name: libfoo
     version: 2.0.0
     summary: Modern C++ parser
     license: LGPLv2
+    build-email: foo@example.com
+    build-warning-email: warning@example.com
+    build-error-email: error@example.com
     builds: all
     build-include: linux*
     build-include: macos*
     build-include: freebsd*
     build-exclude: *
     default-builds: none
-    network-build-config: config.libfoo.network=true
+    default-build-email:
     network-builds: all
     network-build-include: windows*
     network-build-exclude: *
-    cache-build-config: config.libfoo.cache=true config.libfoo.buffer=1028
+    network-build-config: config.libfoo.network=true
+    network-build-warning-email: network-warning@example.com
     cache-builds: legacy
     cache-build-include: freebsd*
     cache-build-exclude: *
-    sys-build-config: ?sys:libcrypto
+    cache-build-config: config.libfoo.cache=true config.libfoo.buffer=1028
+    cache-build-error-email: cache-error@example.com
     sys-builds: default
     sys-build-include: linux*
     sys-build-exclude: *
-    older-build-config: ?libbar/1.0.0
+    sys-build-config: ?sys:libcrypto
+    sys-build-email:
     older-builds: none
-    fancy-build-config: config.libfoo.fancy=true
+    older-build-config: ?libbar/1.0.0
+    older-build-email:
     fancy-builds: gcc
-    deprecated-api-build-config: config.libfoo.deprecated_api=true
+    fancy-build-config: config.libfoo.fancy=true
+    fancy-build-email:
     deprecated-api-builds: windows
-    experimental-api-build-config: config.libfoo.experimental_api=true
+    deprecated-api-build-config: config.libfoo.deprecated_api=true
+    deprecated-api-build-email:
     experimental-api-builds: none
+    experimental-api-build-config: config.libfoo.experimental_api=true
+    experimental-api-build-email:
     EOO
 
   : build-config-default
@@ -177,8 +201,8 @@
     version: 2.0.0
     summary: Modern C++ parser
     license: LGPLv2
-    network-build-config: config.libfoo.network=true
     network-builds: all
+    network-build-config: config.libfoo.network=true
     EOI
     : 1
     name: libfoo
@@ -188,8 +212,8 @@
     default-builds: all
     default-build-include: windows*
     default-build-exclude: *
-    network-build-config: config.libfoo.network=true
     network-builds: none
+    network-build-config: config.libfoo.network=true
     EOO
 
   : add-build-config
@@ -208,8 +232,8 @@
     version: 2.0.0
     summary: Modern C++ parser
     license: LGPLv2
-    network-build-config: config.libfoo.network=true
     network-builds: all
+    network-build-config: config.libfoo.network=true
     experimental-api-build-config: config.libfoo.experimental_api=true
     EOO
 
@@ -345,4 +369,30 @@
     EOI
     cannot override 'deprecated-api-builds' value: no build package configuration 'deprecated-api'
     EOE
+
+  : config-email-after-email
+  :
+  $* 'build-email: foo@example.com' 'network-build-warning-email: warning@example.com' <<EOI 2>>EOE != 0
+    : 1
+    name: libfoo
+    version: 2.0.0
+    summary: Modern C++ parser
+    license: LGPLv2
+    network-build-config: config.libfoo.network=true
+    EOI
+    'network-build-warning-email' override specified together with 'build-email' override
+    EOE
+
+  : email-after-config-email
+  :
+  $* 'network-build-warning-email: warning@example.com' 'build-email: foo@example.com' <<EOI 2>>EOE != 0
+    : 1
+    name: libfoo
+    version: 2.0.0
+    summary: Modern C++ parser
+    license: LGPLv2
+    network-build-config: config.libfoo.network=true
+    EOI
+    'build-email' override specified together with 'network-build-warning-email' override
+    EOE
 }