Implement single quote support

4 files changed, 47 insertions, 5 deletions

diff --git a/build/bootstrap.build b/build/bootstrap.build
index 381b45e..05aac3e 100644
--- a/build/bootstrap.build
+++ b/build/bootstrap.build
@@ -4,3 +4,4 @@
 project = build2
 subprojects = # No subprojects.
 using config
+using test
diff --git a/build/lexer b/build/lexer
index e5676cc..9a0582d 100644
--- a/build/lexer
+++ b/build/lexer
@@ -61,7 +61,10 @@ namespace build
 
   private:
     token
-    name (xchar, bool separated);
+    name (bool separated);
+
+    void
+    single_quote (std::string& lexeme);
 
     // Return true we have seen any spaces. Skipped empty lines don't
     // count. In other words, we are only interested in spaces that
diff --git a/build/lexer.cxx b/build/lexer.cxx
index 88628d3..4151087 100644
--- a/build/lexer.cxx
+++ b/build/lexer.cxx
@@ -94,17 +94,20 @@ namespace build
 
     // Otherwise it is a name.
     //
-    return name (c, sep);
+    unget (c);
+    return name (sep);
   }
 
   token lexer::
-  name (xchar c, bool sep)
+  name (bool sep)
   {
+    xchar c (peek ());
+    assert (!eos (c));
+
     uint64_t ln (c.line), cn (c.column);
     string lexeme;
-    lexeme += (c != '\\' ? c : escape ());
 
-    for (c = peek (); !eos (c); c = peek ())
+    for (; !eos (c); c = peek ())
     {
       bool done (false);
 
@@ -173,6 +176,11 @@ namespace build
           lexeme += escape ();
           break;
         }
+      case '\'':
+        {
+          single_quote (lexeme);
+          break;
+        }
       default:
         {
           get ();
@@ -185,12 +193,35 @@ namespace build
         break;
     }
 
+    // The first character shall not be a separator (we shouldn't have
+    // been called if that's the case).
+    //
+    assert (c.line != ln || c.column != cn);
+
     if (mode_ == lexer_mode::variable)
       next_mode_ = prev_mode_;
 
     return token (lexeme, sep, ln, cn);
   }
 
+  // Assuming the next character is the opening single quote, scan
+  // the stream until the closing quote (or eos), accumulating
+  // characters in between in lexeme. Fail if eos is reached before
+  // the closing quote.
+  //
+  void lexer::
+  single_quote (string& lexeme)
+  {
+    xchar c (get ()); // Opening quote mark.
+    assert (c == '\'');
+
+    for (c = get (); !eos (c) && c != '\''; c = get ())
+      lexeme += c;
+
+    if (eos (c))
+      fail (c) << "unterminated single-quoted sequence";
+  }
+
   bool lexer::
   skip_spaces ()
   {
diff --git a/build/root.build b/build/root.build
index 5af4637..1afbe80 100644
--- a/build/root.build
+++ b/build/root.build
@@ -11,3 +11,10 @@ cxx.ext = cxx
 
 cxx.std = 14
 cxx.poptions += -I$src_root
+
+# All exe{} in tests/ are, well, tests.
+#
+tests/:
+{
+  test.exe = true
+}