Add buildscript depdb builtin 'env' command

4 files changed, 29 insertions, 12 deletions

diff --git a/libbuild2/script/parser.cxx b/libbuild2/script/parser.cxx
index 41d3092..ebfd5fc 100644
--- a/libbuild2/script/parser.cxx
+++ b/libbuild2/script/parser.cxx
@@ -1437,7 +1437,7 @@ namespace build2
         }
         else if (optional<string> v = str ("--unset", "-u"))
         {
-          verify_environment_var_name (*v, o.c_str (), "env: ", i->second);
+          verify_environment_var_name (*v, "env: ", i->second, o.c_str ());
 
           r.variables.add (move (*v));
         }
diff --git a/libbuild2/script/run.cxx b/libbuild2/script/run.cxx
index 3faa35c..f36e979 100644
--- a/libbuild2/script/run.cxx
+++ b/libbuild2/script/run.cxx
@@ -781,7 +781,7 @@ namespace build2
         //
         auto verify_name = [&ll] (const string& name, const char* opt)
         {
-          verify_environment_var_name (name, opt, "export: ", ll);
+          verify_environment_var_name (name, "export: ", ll, opt);
         };
 
         // Parse options (variable set/unset cleanups and unsets).
diff --git a/libbuild2/script/script.cxx b/libbuild2/script/script.cxx
index db53418..298d71f 100644
--- a/libbuild2/script/script.cxx
+++ b/libbuild2/script/script.cxx
@@ -818,18 +818,34 @@ namespace build2
     //
     void
     verify_environment_var_name (const string& name,
-                                 const char* opt,
                                  const char* prefix,
-                                 const location& l)
+                                 const location& l,
+                                 const char* opt)
     {
       if (name.empty ())
-        fail (l) << prefix << "empty value for option " << opt;
+      {
+        diag_record dr (fail (l));
+        dr << prefix << "empty ";
+
+        if (opt == nullptr)
+          dr << "variable name";
+        else
+          dr << "value for option " << opt;
+      }
 
       if (name.find ('=') != string::npos)
-        fail (l) << prefix << "invalid value '" << name << "' for option "
-                 << opt << ": contains '='";
-    }
+      {
+        diag_record dr (fail (l));
+        dr << prefix << "invalid ";
+
+        if (opt == nullptr)
+          dr << "variable name '" << name << "'";
+        else
+          dr << "value '" << name << "' for option " << opt;
 
+        dr << ": contains '='";
+      }
+    }
 
     void
     verify_environment_var_assignment (const string& var,
diff --git a/libbuild2/script/script.hxx b/libbuild2/script/script.hxx
index b4cb7fc..dd31e33 100644
--- a/libbuild2/script/script.hxx
+++ b/libbuild2/script/script.hxx
@@ -569,14 +569,15 @@ namespace build2
 
     // Helpers.
     //
-    // Issue diagnostics with the specified prefix and fail if the string is
-    // not a valid variable name or assignment (empty, etc).
+    // Issue diagnostics with the specified prefix and fail if the string
+    // (potentially an option value) is not a valid variable name or
+    // assignment (empty, etc).
     //
     void
     verify_environment_var_name (const string&,
-                                 const char* opt,
                                  const char* prefix,
-                                 const location&);
+                                 const location&,
+                                 const char* opt = nullptr);
 
     void
     verify_environment_var_assignment (const string&,