* shebang handling
@ 2021-07-04 22:09 Mark Wielaard
2021-07-04 22:09 ` [PATCH 1/2] Handle shebang line, plus any whitespace and comment skipping in lexer Mark Wielaard
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Mark Wielaard @ 2021-07-04 22:09 UTC (permalink / raw)
To: gcc-rust
Hi,
Shebang handling, the first line starting with #! was not done fully
correct and it isn't necessary to keep track of the shebang line in
the AST or HIR Crate classes.
Because an inner attribute also starts with #! the first line isn't
regarded as a shebang line if the #! is followed by (optional)
whitespace and comments and a [. In that case the #! is seen as the
start of an inner attribute.
I added various testcases that hopefully show the funny things you can
get when the first line starts with #!.
[PATCH 1/2] Handle shebang line, plus any whitespace and comment
[PATCH 2/2] Remove has_shebang flag from AST and HIR Crate classes
Patches can also be found here:
https://code.wildebeest.org/git/user/mjw/gccrs/log/?h=shebang
Cheers,
Mark
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH 1/2] Handle shebang line, plus any whitespace and comment skipping in lexer
2021-07-04 22:09 shebang handling Mark Wielaard
@ 2021-07-04 22:09 ` Mark Wielaard
2021-07-04 22:09 ` [PATCH 2/2] Remove has_shebang flag from AST and HIR Crate classes Mark Wielaard
2021-07-05 5:46 ` shebang handling Marc
2 siblings, 0 replies; 4+ messages in thread
From: Mark Wielaard @ 2021-07-04 22:09 UTC (permalink / raw)
To: gcc-rust; +Cc: Mark Wielaard
The lexer tried to handle the shebang line but used loc directly,
instead of the current_column. And it assumed a '/' should immediately
follow the "#!". But if the "#!" is followed by whitespace and/or
comments and a '[' character, then the first line isn't see as a
shebang line (even if the kernel or shell would) but as the start of
an inner attribute.
Add various tests for when the first line starting with "#!" is seen
as a shebang line (and should be skipped). And some tests there is a
'[' character following some whitespace and/or comments and the "#!"
is seen as part of an inner attribute.
---
gcc/rust/lex/rust-lex.cc | 79 ++++++++++++++-----
.../rust/compile/torture/not_shebang.rs | 3 +
| 1 +
| 3 +
| 7 ++
.../compile/torture/not_shebang_spaces.rs | 6 ++
gcc/testsuite/rust/compile/torture/shebang.rs | 3 +
.../rust/compile/torture/shebang_plus_attr.rs | 3 +
.../compile/torture/shebang_plus_attr2.rs | 3 +
9 files changed, 89 insertions(+), 19 deletions(-)
create mode 100644 gcc/testsuite/rust/compile/torture/not_shebang.rs
create mode 100644 gcc/testsuite/rust/compile/torture/not_shebang_block_comment.rs
create mode 100644 gcc/testsuite/rust/compile/torture/not_shebang_comment.rs
create mode 100644 gcc/testsuite/rust/compile/torture/not_shebang_multiline_comment.rs
create mode 100644 gcc/testsuite/rust/compile/torture/not_shebang_spaces.rs
create mode 100755 gcc/testsuite/rust/compile/torture/shebang.rs
create mode 100755 gcc/testsuite/rust/compile/torture/shebang_plus_attr.rs
create mode 100755 gcc/testsuite/rust/compile/torture/shebang_plus_attr2.rs
diff --git a/gcc/rust/lex/rust-lex.cc b/gcc/rust/lex/rust-lex.cc
index d1384168731..ebd69de0fd1 100644
--- a/gcc/rust/lex/rust-lex.cc
+++ b/gcc/rust/lex/rust-lex.cc
@@ -237,28 +237,63 @@ Lexer::build_token ()
current_char = peek_input ();
skip_input ();
- // return end of file token if end of file
- if (current_char == EOF)
- return Token::make (END_OF_FILE, loc);
-
// detect shebang
- if (loc == 1 && current_line == 1 && current_char == '#')
+ // Must be the first thing on the first line, starting with #!
+ // But since an attribute can also start with an #! we don't count it as a
+ // shebang line when after any whitespace or comments there is a [. If it
+ // is a shebang line we simple drop the line. Otherwise we don't consume
+ // any characters and fall through to the real tokenizer.
+ if (current_line == 1 && current_column == 1 && current_char == '#'
+ && peek_input () == '!')
{
- current_char = peek_input ();
-
- if (current_char == '!')
+ int n = 1;
+ while (true)
{
- skip_input ();
- current_char = peek_input ();
-
- if (current_char == '/')
+ int next_char = peek_input (n);
+ if (is_whitespace (next_char))
+ n++;
+ else if (next_char == '/' && peek_input (n + 1) == '/')
{
- // definitely shebang
-
- skip_input ();
-
- // ignore rest of line
- while (current_char != '\n')
+ // A single line comment
+ n += 2;
+ next_char = peek_input (n);
+ while (next_char != '\n' && next_char != EOF)
+ {
+ n++;
+ next_char = peek_input (n);
+ }
+ if (next_char == '\n')
+ n++;
+ }
+ else if (next_char == '/' && peek_input (n + 1) == '*')
+ {
+ // Start of a block comment
+ n += 2;
+ int level = 1;
+ while (level > 0)
+ {
+ if (peek_input (n) == EOF)
+ break;
+ else if (peek_input (n) == '/'
+ && peek_input (n + 1) == '*')
+ {
+ n += 2;
+ level += 1;
+ }
+ else if (peek_input (n) == '*'
+ && peek_input (n + 1) == '/')
+ {
+ n += 2;
+ level -= 1;
+ }
+ else
+ n++;
+ }
+ }
+ else if (next_char != '[')
+ {
+ // definitely shebang, ignore the first line
+ while (current_char != '\n' && current_char != EOF)
{
current_char = peek_input ();
skip_input ();
@@ -269,11 +304,17 @@ Lexer::build_token ()
current_column = 1;
// tell line_table that new line starts
line_map->start_line (current_line, max_column_hint);
- continue;
+ break;
}
+ else
+ break; /* Definitely not a shebang line. */
}
}
+ // return end of file token if end of file
+ if (current_char == EOF)
+ return Token::make (END_OF_FILE, loc);
+
// if not end of file, start tokenising
switch (current_char)
{
diff --git a/gcc/testsuite/rust/compile/torture/not_shebang.rs b/gcc/testsuite/rust/compile/torture/not_shebang.rs
new file mode 100644
index 00000000000..37e01b65940
--- /dev/null
+++ b/gcc/testsuite/rust/compile/torture/not_shebang.rs
@@ -0,0 +1,3 @@
+#!
+[allow(unused)]
+fn main () { }
--git a/gcc/testsuite/rust/compile/torture/not_shebang_block_comment.rs b/gcc/testsuite/rust/compile/torture/not_shebang_block_comment.rs
new file mode 100644
index 00000000000..662f6506749
--- /dev/null
+++ b/gcc/testsuite/rust/compile/torture/not_shebang_block_comment.rs
@@ -0,0 +1 @@
+#!/*/this/is/a/comment*/[allow(unused)] fn main () { }
--git a/gcc/testsuite/rust/compile/torture/not_shebang_comment.rs b/gcc/testsuite/rust/compile/torture/not_shebang_comment.rs
new file mode 100644
index 00000000000..273ae4e8e2a
--- /dev/null
+++ b/gcc/testsuite/rust/compile/torture/not_shebang_comment.rs
@@ -0,0 +1,3 @@
+#!//this/is/a/comment
+[allow(unused)]
+fn main () { }
--git a/gcc/testsuite/rust/compile/torture/not_shebang_multiline_comment.rs b/gcc/testsuite/rust/compile/torture/not_shebang_multiline_comment.rs
new file mode 100644
index 00000000000..86800b14cb3
--- /dev/null
+++ b/gcc/testsuite/rust/compile/torture/not_shebang_multiline_comment.rs
@@ -0,0 +1,7 @@
+#!//this/is/a/comment
+
+/* Also a /* nested */
+ multiline // comment
+ with some more whitespace after, but then finally a [, so not a real #! line. */
+
+[allow(unused)] fn main () { }
diff --git a/gcc/testsuite/rust/compile/torture/not_shebang_spaces.rs b/gcc/testsuite/rust/compile/torture/not_shebang_spaces.rs
new file mode 100644
index 00000000000..6b94a69111a
--- /dev/null
+++ b/gcc/testsuite/rust/compile/torture/not_shebang_spaces.rs
@@ -0,0 +1,6 @@
+#!
+
+ [allow(unused)]
+
+ fn main () { }
+
diff --git a/gcc/testsuite/rust/compile/torture/shebang.rs b/gcc/testsuite/rust/compile/torture/shebang.rs
new file mode 100755
index 00000000000..1c8b9c9a955
--- /dev/null
+++ b/gcc/testsuite/rust/compile/torture/shebang.rs
@@ -0,0 +1,3 @@
+#!/usr/bin/env cat
+
+fn main () { }
diff --git a/gcc/testsuite/rust/compile/torture/shebang_plus_attr.rs b/gcc/testsuite/rust/compile/torture/shebang_plus_attr.rs
new file mode 100755
index 00000000000..075bc6cf594
--- /dev/null
+++ b/gcc/testsuite/rust/compile/torture/shebang_plus_attr.rs
@@ -0,0 +1,3 @@
+#!/usr/bin/env cat
+#![allow(unused)]
+fn main () { }
diff --git a/gcc/testsuite/rust/compile/torture/shebang_plus_attr2.rs b/gcc/testsuite/rust/compile/torture/shebang_plus_attr2.rs
new file mode 100755
index 00000000000..ece8a52381c
--- /dev/null
+++ b/gcc/testsuite/rust/compile/torture/shebang_plus_attr2.rs
@@ -0,0 +1,3 @@
+#!//usr/bin/env cat
+#![allow(unused)]
+fn main () { }
--
2.32.0
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH 2/2] Remove has_shebang flag from AST and HIR Crate classes
2021-07-04 22:09 shebang handling Mark Wielaard
2021-07-04 22:09 ` [PATCH 1/2] Handle shebang line, plus any whitespace and comment skipping in lexer Mark Wielaard
@ 2021-07-04 22:09 ` Mark Wielaard
2021-07-05 5:46 ` shebang handling Marc
2 siblings, 0 replies; 4+ messages in thread
From: Mark Wielaard @ 2021-07-04 22:09 UTC (permalink / raw)
To: gcc-rust; +Cc: Mark Wielaard
The lexer deals with the shebang and the parser cannot detect whether
there is or isn't a shebang line. The flag isn't relevant or useful in
the AST and HIR Crate classes.
---
gcc/rust/ast/rust-ast-full-test.cc | 5 +----
gcc/rust/ast/rust-ast.h | 13 +++++--------
gcc/rust/hir/rust-ast-lower.cc | 3 +--
gcc/rust/hir/tree/rust-hir-full-test.cc | 6 +-----
gcc/rust/hir/tree/rust-hir.h | 14 +++++---------
gcc/rust/parse/rust-parse-impl.h | 12 +++++-------
6 files changed, 18 insertions(+), 35 deletions(-)
diff --git a/gcc/rust/ast/rust-ast-full-test.cc b/gcc/rust/ast/rust-ast-full-test.cc
index 3d339ad1aed..12ef255bcbf 100644
--- a/gcc/rust/ast/rust-ast-full-test.cc
+++ b/gcc/rust/ast/rust-ast-full-test.cc
@@ -172,13 +172,10 @@ Crate::as_string () const
rust_debug ("beginning crate recursive as-string");
std::string str ("Crate: ");
- // add utf8bom and shebang
+ // add utf8bom
if (has_utf8bom)
str += "\n has utf8bom";
- if (has_shebang)
- str += "\n has shebang";
-
// inner attributes
str += append_attributes (inner_attrs, INNER);
diff --git a/gcc/rust/ast/rust-ast.h b/gcc/rust/ast/rust-ast.h
index 0e25de2be5c..ce55e1beb5e 100644
--- a/gcc/rust/ast/rust-ast.h
+++ b/gcc/rust/ast/rust-ast.h
@@ -1551,7 +1551,6 @@ protected:
struct Crate
{
bool has_utf8bom;
- bool has_shebang;
std::vector<Attribute> inner_attrs;
// dodgy spacing required here
@@ -1564,17 +1563,16 @@ struct Crate
public:
// Constructor
Crate (std::vector<std::unique_ptr<Item> > items,
- std::vector<Attribute> inner_attrs, bool has_utf8bom = false,
- bool has_shebang = false)
- : has_utf8bom (has_utf8bom), has_shebang (has_shebang),
- inner_attrs (std::move (inner_attrs)), items (std::move (items)),
+ std::vector<Attribute> inner_attrs, bool has_utf8bom = false)
+ : has_utf8bom (has_utf8bom), inner_attrs (std::move (inner_attrs)),
+ items (std::move (items)),
node_id (Analysis::Mappings::get ()->get_next_node_id ())
{}
// Copy constructor with vector clone
Crate (Crate const &other)
- : has_utf8bom (other.has_utf8bom), has_shebang (other.has_shebang),
- inner_attrs (other.inner_attrs), node_id (other.node_id)
+ : has_utf8bom (other.has_utf8bom), inner_attrs (other.inner_attrs),
+ node_id (other.node_id)
{
items.reserve (other.items.size ());
for (const auto &e : other.items)
@@ -1587,7 +1585,6 @@ public:
Crate &operator= (Crate const &other)
{
inner_attrs = other.inner_attrs;
- has_shebang = other.has_shebang;
has_utf8bom = other.has_utf8bom;
node_id = other.node_id;
diff --git a/gcc/rust/hir/rust-ast-lower.cc b/gcc/rust/hir/rust-ast-lower.cc
index c7222e2e998..0f3c86dc7bf 100644
--- a/gcc/rust/hir/rust-ast-lower.cc
+++ b/gcc/rust/hir/rust-ast-lower.cc
@@ -41,7 +41,6 @@ ASTLowering::go ()
{
std::vector<std::unique_ptr<HIR::Item> > items;
bool has_utf8bom = false;
- bool has_shebang = false;
for (auto it = astCrate.items.begin (); it != astCrate.items.end (); it++)
{
@@ -57,7 +56,7 @@ ASTLowering::go ()
UNKNOWN_LOCAL_DEFID);
return HIR::Crate (std::move (items), astCrate.get_inner_attrs (), mapping,
- has_utf8bom, has_shebang);
+ has_utf8bom);
}
// rust-ast-lower-block.h
diff --git a/gcc/rust/hir/tree/rust-hir-full-test.cc b/gcc/rust/hir/tree/rust-hir-full-test.cc
index 261b3af672a..051ba8736ad 100644
--- a/gcc/rust/hir/tree/rust-hir-full-test.cc
+++ b/gcc/rust/hir/tree/rust-hir-full-test.cc
@@ -73,15 +73,11 @@ std::string
Crate::as_string () const
{
std::string str ("HIR::Crate: ");
- // add utf8bom and shebang
+ // add utf8bom
if (has_utf8bom)
{
str += "\n has utf8bom";
}
- if (has_shebang)
- {
- str += "\n has shebang";
- }
// inner attributes
str += "\n inner attributes: ";
diff --git a/gcc/rust/hir/tree/rust-hir.h b/gcc/rust/hir/tree/rust-hir.h
index 35dc71ae1df..f918f2dc106 100644
--- a/gcc/rust/hir/tree/rust-hir.h
+++ b/gcc/rust/hir/tree/rust-hir.h
@@ -679,7 +679,6 @@ public:
struct Crate
{
bool has_utf8bom;
- bool has_shebang;
AST::AttrVec inner_attrs;
// dodgy spacing required here
@@ -692,17 +691,15 @@ struct Crate
public:
// Constructor
Crate (std::vector<std::unique_ptr<Item> > items, AST::AttrVec inner_attrs,
- Analysis::NodeMapping mappings, bool has_utf8bom = false,
- bool has_shebang = false)
- : has_utf8bom (has_utf8bom), has_shebang (has_shebang),
- inner_attrs (std::move (inner_attrs)), items (std::move (items)),
- mappings (mappings)
+ Analysis::NodeMapping mappings, bool has_utf8bom = false)
+ : has_utf8bom (has_utf8bom), inner_attrs (std::move (inner_attrs)),
+ items (std::move (items)), mappings (mappings)
{}
// Copy constructor with vector clone
Crate (Crate const &other)
- : has_utf8bom (other.has_utf8bom), has_shebang (other.has_shebang),
- inner_attrs (other.inner_attrs), mappings (other.mappings)
+ : has_utf8bom (other.has_utf8bom), inner_attrs (other.inner_attrs),
+ mappings (other.mappings)
{
items.reserve (other.items.size ());
for (const auto &e : other.items)
@@ -715,7 +712,6 @@ public:
Crate &operator= (Crate const &other)
{
inner_attrs = other.inner_attrs;
- has_shebang = other.has_shebang;
has_utf8bom = other.has_utf8bom;
mappings = other.mappings;
diff --git a/gcc/rust/parse/rust-parse-impl.h b/gcc/rust/parse/rust-parse-impl.h
index 9f8282b3639..136b34371f1 100644
--- a/gcc/rust/parse/rust-parse-impl.h
+++ b/gcc/rust/parse/rust-parse-impl.h
@@ -393,12 +393,11 @@ template <typename ManagedTokenSource>
AST::Crate
Parser<ManagedTokenSource>::parse_crate ()
{
- /* TODO: determine if has utf8bom and shebang. Currently, they are eliminated
- * by the lexing phase. Neither are useful for the compiler anyway, so maybe a
+ /* TODO: determine if has utf8bom. Currently, is eliminated
+ * by the lexing phase. Not useful for the compiler anyway, so maybe a
* better idea would be to eliminate
- * the has_utf8bom and has_shebang variables from the crate data structure. */
+ * the has_utf8bom variable from the crate data structure. */
bool has_utf8bom = false;
- bool has_shebang = false;
// parse inner attributes
AST::AttrVec inner_attrs = parse_inner_attributes ();
@@ -430,8 +429,7 @@ Parser<ManagedTokenSource>::parse_crate ()
for (const auto &error : error_table)
error.emit_error ();
- return AST::Crate (std::move (items), std::move (inner_attrs), has_utf8bom,
- has_shebang);
+ return AST::Crate (std::move (items), std::move (inner_attrs), has_utf8bom);
}
// Parse a contiguous block of inner attributes.
@@ -484,7 +482,7 @@ Parser<ManagedTokenSource>::parse_inner_attribute ()
if (lexer.peek_token ()->get_id () != EXCLAM)
{
Error error (lexer.peek_token ()->get_locus (),
- "expected %<!%> or %<[%> for inner attribute or shebang");
+ "expected %<!%> or %<[%> for inner attribute");
add_error (std::move (error));
return AST::Attribute::create_empty ();
--
2.32.0
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: shebang handling
2021-07-04 22:09 shebang handling Mark Wielaard
2021-07-04 22:09 ` [PATCH 1/2] Handle shebang line, plus any whitespace and comment skipping in lexer Mark Wielaard
2021-07-04 22:09 ` [PATCH 2/2] Remove has_shebang flag from AST and HIR Crate classes Mark Wielaard
@ 2021-07-05 5:46 ` Marc
2 siblings, 0 replies; 4+ messages in thread
From: Marc @ 2021-07-05 5:46 UTC (permalink / raw)
To: Mark Wielaard; +Cc: gcc-rust
Mark Wielaard <mark@klomp.org> writes:
> [PATCH 1/2] Handle shebang line, plus any whitespace and comment
> [PATCH 2/2] Remove has_shebang flag from AST and HIR Crate classes
Pushed to githup:
https://github.com/Rust-GCC/gccrs/pull/546
Marc
^ permalink raw reply [flat|nested] 4+ messages in thread
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2021-07-04 22:09 shebang handling Mark Wielaard
2021-07-04 22:09 ` [PATCH 1/2] Handle shebang line, plus any whitespace and comment skipping in lexer Mark Wielaard
2021-07-04 22:09 ` [PATCH 2/2] Remove has_shebang flag from AST and HIR Crate classes Mark Wielaard
2021-07-05 5:46 ` shebang handling Marc
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