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-rw-r--r--libbuild2/parser.cxx189
1 files changed, 111 insertions, 78 deletions
diff --git a/libbuild2/parser.cxx b/libbuild2/parser.cxx
index 9e586e0..be1ba0b 100644
--- a/libbuild2/parser.cxx
+++ b/libbuild2/parser.cxx
@@ -287,11 +287,15 @@ namespace build2
{
tracer trace ("parser::parse_clause", &path_);
- // parse_clause() should always stop at a token that is at the beginning
- // of the line (except for eof). That is, if something is called to parse
- // a line, it should parse it until newline (or fail). This is important
- // for if-else blocks, directory scopes, etc., that assume the '}' token
- // they see is on the new line.
+ // This function should be called in the normal lexing mode with the first
+ // token of a line or an alternative arrangements may have to be made to
+ // recognize the attributes.
+ //
+ // It should also always stop at a token that is at the beginning of the
+ // line (except for eof). That is, if something is called to parse a line,
+ // it should parse it until newline (or fail). This is important for
+ // if-else blocks, directory scopes, etc., that assume the '}' token they
+ // see is on the new line.
//
bool parsed (false);
@@ -302,8 +306,7 @@ namespace build2
assert (attributes_.empty ());
auto at (attributes_push (t, tt));
- // We should always start with one or more names, potentially
- // <>-grouped.
+ // We always start with one or more names, potentially <>-grouped.
//
if (!(start_names (tt) || tt == type::labrace))
{
@@ -454,6 +457,13 @@ namespace build2
{
// Parse target names inside < >.
//
+ // We "reserve" the right to have attributes inside <> though what
+ // exactly that would mean is unclear. One potentially useful
+ // semantics would be the ability to specify attributes for ad hoc
+ // members though the fact that the primary target is listed first
+ // would make it rather unintuitive.
+ //
+ enable_attributes ();
next (t, tt);
auto at (attributes_push (t, tt));
@@ -621,7 +631,10 @@ namespace build2
}
};
- if (next (t, tt) == type::newline)
+ enable_attributes (); // Recognize attributes after `:`.
+ next (t, tt);
+
+ if (tt == type::newline)
{
// See if this is a target block.
//
@@ -734,85 +747,70 @@ namespace build2
//
// This can take any of the following forms:
//
- // x = y
- // foo/ x = y (ns will have two elements)
- // foo/ [attrs] x = y (tt will be '[')
+ // x = y
+ // foo/ x = y (ns will have two elements)
+ //
+ // And in the future we may also want to support:
+ //
+ // foo/ bar/ x = y
//
- // In the future we may also want to support:
+ // Note that we don't support this:
//
- // foo/ bar/ x = y
+ // foo/ [attrs] x = y
//
- if (tt == type::assign || tt == type::prepend || tt == type::append ||
- tt == type::lsbrace)
+ // Because the meaning of `[attrs]` would be ambiguous (it could also be
+ // a name). Note that the above semantics can be easily achieved with an
+ // explicit directory scope:
+ //
+ // foo/
+ // {
+ // [attrs] x = y
+ // }
+ //
+ if (tt == type::assign || tt == type::prepend || tt == type::append)
{
// Detect and handle the directory scope. If things look off, then we
// let parse_variable_name() complain.
//
dir_path d;
-
- if ((ns.size () == 2 && ns[0].directory ()) ||
- (ns.size () == 1 && ns[0].directory () && tt == type::lsbrace))
+ if (ns.size () == 2 && ns[0].directory ())
{
if (at.first)
fail (at.second) << "attributes before scope directory";
- if (tt == type::lsbrace)
- {
- attributes_pop ();
- attributes_push (t, tt);
-
- d = move (ns[0].dir);
- nloc = get_location (t);
- ns = parse_names (t, tt, pattern_mode::ignore);
+ d = move (ns[0].dir);
+ ns.erase (ns.begin ());
- // It got to be a variable assignment.
- //
- if (tt != type::assign &&
- tt != type::prepend &&
- tt != type::append)
- fail (t) << "expected variable assignment instead of " << t;
- }
- else
- {
- d = move (ns[0].dir);
- ns.erase (ns.begin ());
- }
+ // Make sure it's not a pattern (see also the target case above and
+ // scope below).
+ //
+ if (path_pattern (d))
+ fail (nloc) << "pattern in directory " << d.representation ();
}
- // Make sure not a pattern (see also the target case above and scope
- // below).
- //
- if (path_pattern (d))
- fail (nloc) << "pattern in directory " << d.representation ();
+ const variable& var (parse_variable_name (move (ns), nloc));
+ apply_variable_attributes (var);
- if (tt != type::lsbrace)
+ if (var.visibility >= variable_visibility::target)
{
- const variable& var (parse_variable_name (move (ns), nloc));
- apply_variable_attributes (var);
+ diag_record dr (fail (nloc));
- if (var.visibility >= variable_visibility::target)
- {
- diag_record dr (fail (nloc));
+ dr << "variable " << var << " has " << var.visibility
+ << " visibility but is assigned on a scope";
- dr << "variable " << var << " has " << var.visibility
- << " visibility but is assigned on a scope";
-
- if (var.visibility == variable_visibility::target)
- dr << info << "consider changing it to '*: " << var << "'";
- }
-
- {
- enter_scope sg (d.empty ()
- ? enter_scope ()
- : enter_scope (*this, move (d)));
- parse_variable (t, tt, var, tt);
- }
+ if (var.visibility == variable_visibility::target)
+ dr << info << "consider changing it to '*: " << var << "'";
+ }
- next_after_newline (t, tt);
- continue;
+ {
+ enter_scope sg (d.empty ()
+ ? enter_scope ()
+ : enter_scope (*this, move (d)));
+ parse_variable (t, tt, var, tt);
}
- // Not "our" attribute, see if anyone else likes it.
+ next_after_newline (t, tt);
+ continue;
}
// See if this is a directory scope.
@@ -873,7 +871,7 @@ namespace build2
// Parse a target or prerequisite-specific variable block. If type is not
// NULL, then this is a target type/pattern-specific block.
//
- // enter: first token of first line in the block
+ // enter: first token of first line in the block (normal lexer mode)
// leave: rcbrace
//
// This is a more restricted variant of parse_clause() that only allows
@@ -1216,7 +1214,9 @@ namespace build2
fail (ploc) << "no prerequisites in dependency chain or prerequisite-"
<< "specific variable assignment";
+ enable_attributes (); // Recognize attributes after `:`.
next (t, tt);
+
auto at (attributes_push (t, tt));
// @@ PAT: currently we pattern-expand prerequisite-specific vars.
@@ -1670,6 +1670,7 @@ namespace build2
// manually looking for =/=+/+=.
//
mode (lexer_mode::value, '@');
+ enable_attributes (); // @@ VAL.
next (t, tt);
// Get variable attributes, if any (note that here we will go into a
@@ -1820,6 +1821,7 @@ namespace build2
// being able to type them or to return NULL.
//
mode (lexer_mode::value, '@');
+ enable_attributes (); // @@ VAL.
next (t, tt);
auto at (attributes_push (t, tt));
@@ -1971,6 +1973,8 @@ namespace build2
for (;;)
{
string k (move (t.value));
+
+ enable_attributes (); // Recognize attributes before value.
next (t, tt);
bool take (false); // Take this branch?
@@ -2131,7 +2135,9 @@ namespace build2
do
{
+ enable_attributes (); // Recognize attributes before value.
next (t, tt);
+
if (tt == type::newline || tt == type::eos)
fail (t) << "expected switch expression instead of " << t;
@@ -2237,7 +2243,7 @@ namespace build2
//
mode (lexer_mode::case_patterns); // Recognize `|` and `,`.
- auto parse_pattern = [this] (token& t, type& tt)
+ auto parse_pattern_with_attributes = [this] (token& t, type& tt)
{
return parse_value_with_attributes (
t, tt, pattern_mode::ignore, "pattern", nullptr);
@@ -2245,7 +2251,9 @@ namespace build2
for (size_t i (0);; ++i)
{
+ enable_attributes (); // Recognize attributes before pattern.
next (t, tt);
+
if (tt == type::newline || tt == type::eos)
fail (t) << "expected case pattern instead of " << t;
@@ -2254,10 +2262,10 @@ namespace build2
// Handle pattern alternatives (<pattern>|<pattern>).
//
- for (;; next (t, tt))
+ for (;;)
{
const location l (get_location (t));
- value p (parse_pattern (t, tt));
+ value p (parse_pattern_with_attributes (t, tt));
expr& e (exprs[i]); // Note: value might be modified (typified).
if (e.func)
@@ -2300,14 +2308,18 @@ namespace build2
pre_parse_ = true;
do
{
+ enable_attributes (); // Recognize attributes before pattern.
next (t, tt); // Skip `|`.
- parse_pattern (t, tt);
+ parse_pattern_with_attributes (t, tt);
}
while (tt == type::bit_or);
pre_parse_ = false;
break;
}
+
+ enable_attributes (); // Recognize attributes before pattern.
+ next (t, tt);
}
if (!take)
@@ -2421,6 +2433,7 @@ namespace build2
// First take care of the variable name. There is no reason not to
// support variable attributes.
//
+ enable_attributes ();
next (t, tt);
attributes_push (t, tt);
@@ -2445,6 +2458,7 @@ namespace build2
// value on the RHS of an assignment (expansion, attributes).
//
mode (lexer_mode::value, '@');
+ enable_attributes (); // @@ VAL
next (t, tt);
value val (parse_value_with_attributes (t, tt, pattern_mode::expand));
@@ -2573,6 +2587,7 @@ namespace build2
// condition) for the same reason as in if-else (see parse_if_else()).
//
mode (lexer_mode::value);
+ enable_attributes (); // @@ VAL
next (t, tt);
const location el (get_location (t));
@@ -2627,6 +2642,7 @@ namespace build2
// (expansion, attributes).
//
mode (lexer_mode::value, '@');
+ enable_attributes (); // @@ VAL
next (t, tt);
if (value v = parse_value_with_attributes (t, tt, pattern_mode::expand))
@@ -2660,6 +2676,7 @@ namespace build2
// (expansion, attributes).
//
mode (lexer_mode::value, '@');
+ enable_attributes (); // @@ VAL
next (t, tt);
if (value v = parse_value_with_attributes (t, tt, pattern_mode::expand))
@@ -2862,6 +2879,7 @@ namespace build2
parse_variable_value (token& t, type& tt)
{
mode (lexer_mode::value, '@');
+ enable_attributes (); // @@ VAL.
next (t, tt);
// Parse value attributes if any. Note that it's ok not to have anything
@@ -3121,6 +3139,7 @@ namespace build2
// leave: rparen
mode (lexer_mode::eval, '@'); // Auto-expires at rparen.
+ enable_attributes (); // @@ VAL (eval)
next (t, tt);
if (tt == type::rparen)
@@ -3137,7 +3156,7 @@ namespace build2
values parser::
parse_eval_comma (token& t, type& tt, pattern_mode pmode, bool first)
{
- // enter: first token of LHS
+ // enter: first token of LHS (lexed with enabled attributes)
// leave: next token after last RHS
// Left-associative: parse in a loop for as long as we can.
@@ -3150,7 +3169,9 @@ namespace build2
while (tt == type::comma)
{
+ enable_attributes (); // Recognize attributes before value.
next (t, tt);
+
value rhs (parse_eval_ternary (t, tt, pmode));
if (!pre_parse_)
@@ -3163,7 +3184,7 @@ namespace build2
value parser::
parse_eval_ternary (token& t, type& tt, pattern_mode pmode, bool first)
{
- // enter: first token of LHS
+ // enter: first token of LHS (lexed with enabled attributes)
// leave: next token after last RHS
// Right-associative (kind of): we parse what's between ?: without
@@ -3196,7 +3217,9 @@ namespace build2
if (!pp)
pre_parse_ = !q; // Short-circuit middle?
+ enable_attributes (); // Recognize attributes before value.
next (t, tt);
+
value mhs (parse_eval_ternary (t, tt, pmode));
if (tt != type::colon)
@@ -3205,7 +3228,9 @@ namespace build2
if (!pp)
pre_parse_ = q; // Short-circuit right?
+ enable_attributes (); // Recognize attributes before value.
next (t, tt);
+
value rhs (parse_eval_ternary (t, tt, pmode));
pre_parse_ = pp;
@@ -3215,7 +3240,7 @@ namespace build2
value parser::
parse_eval_or (token& t, type& tt, pattern_mode pmode, bool first)
{
- // enter: first token of LHS
+ // enter: first token of LHS (lexed with enabled attributes)
// leave: next token after last RHS
// Left-associative: parse in a loop for as long as we can.
@@ -3234,7 +3259,9 @@ namespace build2
if (!pre_parse_ && convert<bool> (move (lhs)))
pre_parse_ = true;
+ enable_attributes (); // Recognize attributes before value.
next (t, tt);
+
l = get_location (t);
value rhs (parse_eval_and (t, tt, pmode));
@@ -3255,7 +3282,7 @@ namespace build2
value parser::
parse_eval_and (token& t, type& tt, pattern_mode pmode, bool first)
{
- // enter: first token of LHS
+ // enter: first token of LHS (lexed with enabled attributes)
// leave: next token after last RHS
// Left-associative: parse in a loop for as long as we can.
@@ -3274,7 +3301,9 @@ namespace build2
if (!pre_parse_ && !convert<bool> (move (lhs)))
pre_parse_ = true;
+ enable_attributes (); // Recognize attributes before value.
next (t, tt);
+
l = get_location (t);
value rhs (parse_eval_comp (t, tt, pmode));
@@ -3295,7 +3324,7 @@ namespace build2
value parser::
parse_eval_comp (token& t, type& tt, pattern_mode pmode, bool first)
{
- // enter: first token of LHS
+ // enter: first token of LHS (lexed with enabled attributes)
// leave: next token after last RHS
// Left-associative: parse in a loop for as long as we can.
@@ -3312,7 +3341,9 @@ namespace build2
type op (tt);
location l (get_location (t));
+ enable_attributes (); // Recognize attributes before value.
next (t, tt);
+
value rhs (parse_eval_value (t, tt, pmode));
if (pre_parse_)
@@ -3329,7 +3360,7 @@ namespace build2
value parser::
parse_eval_value (token& t, type& tt, pattern_mode pmode, bool first)
{
- // enter: first token of value
+ // enter: first token of value (lexed with enabled attributes)
// leave: next token after value
// Parse value attributes if any. Note that it's ok not to have anything
@@ -3344,7 +3375,9 @@ namespace build2
{
case type::log_not:
{
+ enable_attributes (); // Recognize attributes before value.
next (t, tt);
+
v = parse_eval_value (t, tt, pmode);
if (pre_parse_)
@@ -3498,7 +3531,7 @@ namespace build2
// Using '@' for attribute key-value pairs would be just too ugly. Seeing
// that we control what goes into keys/values, let's use a much nicer '='.
//
- mode (lexer_mode::attribute, '=');
+ mode (lexer_mode::attributes, '=');
next (t, tt);
has = (tt != type::rsbrace);
@@ -5372,7 +5405,7 @@ namespace build2
// In fact, because this is only done in the buildspec mode, we can still
// use eval contexts provided that we quote them: '"cle(an)"'. Note that
// function calls also need quoting (since a separated '(' is not treated as
- // function call): '"$identity(update)"'.
+ // a function call): '"$identity(update)"'.
//
// This poses a problem, though: if it's quoted then it is a concatenated
// expansion and therefore cannot contain multiple values, for example,