Implement new default target logic, canonical directory name (empty value)

The logic is as follows: if we have an explicit current directory
target, then that's the default target. Otherwise, we take the
first target and use it as a prerequisite to create an implicit
current directory target, effectively making it the default
target via an alias. If there are no targets in this buildfile,
then we don't do anything.

1 files changed, 8 insertions, 0 deletions

diff --git a/build/parser b/build/parser
index 2e399c9..e5aeb60 100644
--- a/build/parser
+++ b/build/parser
@@ -17,6 +17,7 @@
 namespace build
 {
   class scope;
+  class target;
   class lexer;
 
   class parser
@@ -61,6 +62,12 @@ namespace build
     // Utilities.
     //
   private:
+    void
+    process_default_target (token&);
+
+    // Lexer.
+    //
+  private:
     token_type
     next (token&, token_type&);
 
@@ -83,6 +90,7 @@ namespace build
     const std::string* path_; // Path processed by diagnostic_string().
     lexer* lexer_;
     scope* scope_;
+    target* default_target_;
 
     token peek_ {token_type::eos, false, 0, 0};
     bool peeked_ {false};