3 files changed, 132 insertions, 4 deletions
diff --git a/libbuild2/test/script/parser+redirect.test.testscript b/libbuild2/test/script/parser+redirect.test.testscript
index a8691da..49fa89b 100644
--- a/libbuild2/test/script/parser+redirect.test.testscript
+++ b/libbuild2/test/script/parser+redirect.test.testscript
@@ -167,6 +167,92 @@
       }
     }
   }
+
+  : overriding
+  :
+  {
+    : literal
+    :
+    {
+      : with
+      :
+      {
+        : string
+        :
+        $* <<EOI >>EOO
+        cmd >>EOF >bar
+        foo
+        EOF
+        EOI
+        cmd >bar
+        EOO
+
+        : regex
+        :
+        $* <<EOI >>EOO
+        cmd >>FOO >>~/BAR/
+        foo
+        FOO
+        bar
+        BAR
+        EOI
+        cmd >>~/BAR/
+        bar
+        BAR
+        EOO
+
+        : self
+        :
+        $* <<EOI >>EOO
+        cmd >>EOF >>EOF
+        foo
+        EOF
+        EOI
+        cmd >>EOF
+        foo
+        EOF
+        EOO
+
+        : different-modifiers
+        :
+        $* <<EOI 2>>EOE != 0
+        cmd >>EOF >>/EOF
+        foo
+        EOF
+        EOI
+        testscript:1:14: error: different modifiers for shared here-document 'EOF'
+        EOE
+      }
+    }
+
+    : shared
+    :
+    {
+      : after-sharing
+      :
+      $* <<EOI >>EOO
+      cmd >>EOF 2>>EOF >bar
+      foo
+      EOF
+      EOI
+      cmd >bar 2>>EOF
+      foo
+      EOF
+      EOO
+
+      : before-sharing
+      :
+      $* <<EOI >>EOO
+      cmd >>EOF >bar 2>>EOF
+      foo
+      EOF
+      EOI
+      cmd >bar 2>>EOF
+      foo
+      EOF
+      EOO
+    }
+  }
 }
 
 : file
diff --git a/libbuild2/test/script/parser.cxx b/libbuild2/test/script/parser.cxx
index 8b8f705..bc06ce8 100644
--- a/libbuild2/test/script/parser.cxx
+++ b/libbuild2/test/script/parser.cxx
@@ -1657,7 +1657,7 @@ namespace build2
         // Parse the redirect operator.
         //
         auto parse_redirect =
-          [&c, &expr, &p, &mod, this] (token& t, const location& l)
+          [&c, &expr, &p, &mod, &hd, this] (token& t, const location& l)
         {
           // Our semantics is the last redirect seen takes effect.
           //
@@ -1774,6 +1774,8 @@ namespace build2
           }
 
           redirect& r (fd == 0 ? c.in : fd == 1 ? c.out : c.err);
+          redirect_type overriden (r.type);
+
           r = redirect (rt);
 
           // Don't move as still may be used for pending here-document end
@@ -1848,6 +1850,37 @@ namespace build2
 
           case redirect_type::here_doc_ref: assert (false); break;
           }
+
+          // If we are overriding a here-document, then remove the reference
+          // to this command redirect from the corresponding here_doc object.
+          //
+          if (!pre_parse_ &&
+              (overriden == redirect_type::here_doc_literal ||
+               overriden == redirect_type::here_doc_regex))
+          {
+            size_t e (expr.size () - 1);
+            size_t p (expr.back ().pipe.size ());
+            int    f (static_cast<int> (fd));
+
+            for (here_doc& d: hd)
+            {
+              small_vector<here_redirect, 2>& rs (d.redirects);
+
+              auto i (find_if (rs.begin (), rs.end (),
+                               [e, p, f] (const here_redirect& r)
+                               {
+                                 return r.expr == e &&
+                                        r.pipe == p &&
+                                        r.fd   == f;
+                               }));
+
+              if (i != rs.end ())
+              {
+                rs.erase (i);
+                break;
+              }
+            }
+          }
         };
 
         // Set pending cleanup type.
@@ -2483,9 +2516,11 @@ namespace build2
           parsed_doc v (
             parse_here_document (t, tt, h.end, h.modifiers, h.regex));
 
-          if (!pre_parse_)
+          // If all the here-document redirects are overridden, then we just
+          // drop the fragment.
+          //
+          if (!pre_parse_ && !h.redirects.empty ())
           {
-            assert (!h.redirects.empty ());
             auto i (h.redirects.cbegin ());
 
             command& c (p.first[i->expr].pipe[i->pipe]);
@@ -2493,11 +2528,17 @@ namespace build2
 
             if (v.re)
             {
+              assert (r.type == redirect_type::here_doc_regex);
+
               r.regex = move (v.regex);
               r.regex.flags = move (h.regex_flags);
             }
             else
+            {
+              assert (r.type == redirect_type::here_doc_literal);
+
               r.str = move (v.str);
+            }
 
             r.end        = move (h.end);
             r.end_line   = v.end_line;
diff --git a/libbuild2/test/script/parser.hxx b/libbuild2/test/script/parser.hxx
index e4d1f3a..4d3fa49 100644
--- a/libbuild2/test/script/parser.hxx
+++ b/libbuild2/test/script/parser.hxx
@@ -122,7 +122,8 @@ namespace build2
         struct here_doc
         {
           // Redirects that share here_doc. Most of the time we will have no
-          // more than 2 (2 - for the roundtrip test cases).
+          // more than 2 (2 - for the roundtrip test cases). Doesn't refer
+          // overridden redirects and thus can be empty.
           //
           small_vector<here_redirect, 2> redirects;