Auto merge of #1384 - emilio:whitespace-comment, r=fitzgen

ir: Preserve better whitespace in comments.

Fixes #1341.

Author: bors-servo

src/ir/comment.rs

@@ -35,7 +35,6 @@ fn kind(comment: &str) -> Option<Kind> {
 
 fn make_indent(indent: usize) -> String {
     const RUST_INDENTATION: usize = 4;
-
     iter::repeat(' ').take(indent * RUST_INDENTATION).collect()
 }
 
@@ -49,12 +48,11 @@ fn preprocess_single_lines(comment: &str, indent: usize) -> String {
     let mut is_first = true;
     let lines: Vec<_> = comment
         .lines()
-        .map(|l| l.trim_left_matches('/').trim())
+        .map(|l| l.trim().trim_left_matches('/'))
         .map(|l| {
             let indent = if is_first { "" } else { &*indent };
             is_first = false;
-            let maybe_space = if l.is_empty() { "" } else { " " };
-            format!("{}///{}{}", indent, maybe_space, l)
+            format!("{}///{}", indent, l)
         })
         .collect();
     lines.join("\n")
@@ -63,30 +61,24 @@ fn preprocess_single_lines(comment: &str, indent: usize) -> String {
 fn preprocess_multi_line(comment: &str, indent: usize) -> String {
     let comment = comment
         .trim_left_matches('/')
-        .trim_left_matches('*')
-        .trim_left_matches('!')
         .trim_right_matches('/')
-        .trim_right_matches('*')
-        .trim();
+        .trim_right_matches('*');
 
     let indent = make_indent(indent);
     // Strip any potential `*` characters preceding each line.
     let mut is_first = true;
     let mut lines: Vec<_> = comment.lines()
-        .map(|line| line.trim().trim_left_matches('*').trim())
-        .skip_while(|line| line.is_empty()) // Skip the first empty lines.
+        .map(|line| line.trim().trim_left_matches('*').trim_left_matches('!'))
+        .skip_while(|line| line.trim().is_empty()) // Skip the first empty lines.
         .map(|line| {
             let indent = if is_first { "" } else { &*indent };
             is_first = false;
-            let maybe_space = if line.is_empty() { "" } else { " " };
-            format!("{}///{}{}", indent, maybe_space, line)
+            format!("{}///{}", indent, line)
         })
         .collect();
 
     // Remove the trailing line corresponding to the `*/`.
-    let last_line_is_empty = lines.last().map_or(false, |l| l.is_empty());
-
-    if last_line_is_empty {
+    if lines.last().map_or(false, |l| l.trim().is_empty() || l.trim() == "///") {
         lines.pop();
     }
 
@@ -107,6 +99,7 @@ mod test {
     fn processes_single_lines_correctly() {
         assert_eq!(preprocess("/// hello", 0), "/// hello");
         assert_eq!(preprocess("// hello", 0), "/// hello");
+        assert_eq!(preprocess("//    hello", 0), "///    hello");
     }
 
     #[test]
@@ -118,7 +111,7 @@ mod test {
 
         assert_eq!(
             preprocess("/**\nhello\n*world\n*foo\n*/", 0),
-            "/// hello\n/// world\n/// foo"
+            "///hello\n///world\n///foo"
         );
     }
 }

tests/expectations/tests/constify-enum.rs

@@ -19,6 +19,6 @@ pub enum nsCSSPropertyID {
     eCSSProperty_b = 1,
     eCSSPropertyAlias_aa = 2,
     eCSSPropertyAlias_bb = 3,
-    /// < <div rustbindgen constant></div>
+    ///< <div rustbindgen constant></div>
     eCSSProperty_COUNT_unexistingVariantValue = 4,
 }

tests/expectations/tests/convert-cpp-comment-to-rust.rs

@@ -1,19 +1,22 @@
 /* automatically generated by rust-bindgen */
 
-
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
-
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 pub type mbedtls_mpi_uint = ::std::os::raw::c_uint;
 /// \brief          MPI structure
 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
 pub struct mbedtls_mpi {
-    /// <  integer sign
+    ///<  integer sign
     pub s: ::std::os::raw::c_int,
-    /// <  total # of limbs
+    ///<  total # of limbs
     pub n: ::std::os::raw::c_ulong,
-    /// <  pointer to limbs
+    ///<  pointer to limbs
     pub p: *mut mbedtls_mpi_uint,
 }
 #[test]

tests/expectations/tests/enum-doc-bitfield.rs

@@ -1,6 +1,11 @@
 /* automatically generated by rust-bindgen */
 
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 impl B {
     /// Document field with three slashes
@@ -15,11 +20,11 @@ impl B {
     pub const VAR_C: B = B(2);
 }
 impl B {
-    /// < Document field with following star
+    ///< Document field with following star
     pub const VAR_D: B = B(3);
 }
 impl B {
-    /// < Document field with following exclamation
+    ///< Document field with following exclamation
     pub const VAR_E: B = B(4);
 }
 impl B {

tests/expectations/tests/enum-doc-mod.rs

@@ -1,6 +1,11 @@
 /* automatically generated by rust-bindgen */
 
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 pub mod B {
     /// Document enum
@@ -11,9 +16,9 @@ pub mod B {
     pub const VAR_B: Type = 1;
     /// Document field with preceeding exclamation
     pub const VAR_C: Type = 2;
-    /// < Document field with following star
+    ///< Document field with following star
     pub const VAR_D: Type = 3;
-    /// < Document field with following exclamation
+    ///< Document field with following exclamation
     pub const VAR_E: Type = 4;
     /// Document field with preceeding star, with a loong long multiline
     /// comment.

tests/expectations/tests/enum-doc-rusty.rs

@@ -1,6 +1,11 @@
 /* automatically generated by rust-bindgen */
 
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 #[repr(u32)]
 /// Document enum
@@ -12,9 +17,9 @@ pub enum B {
     VAR_B = 1,
     /// Document field with preceeding exclamation
     VAR_C = 2,
-    /// < Document field with following star
+    ///< Document field with following star
     VAR_D = 3,
-    /// < Document field with following exclamation
+    ///< Document field with following exclamation
     VAR_E = 4,
     /// Document field with preceeding star, with a loong long multiline
     /// comment.

tests/expectations/tests/enum-doc.rs

@@ -1,16 +1,21 @@
 /* automatically generated by rust-bindgen */
 
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 /// Document field with three slashes
 pub const B_VAR_A: B = 0;
 /// Document field with preceeding star
 pub const B_VAR_B: B = 1;
 /// Document field with preceeding exclamation
 pub const B_VAR_C: B = 2;
-/// < Document field with following star
+///< Document field with following star
 pub const B_VAR_D: B = 3;
-/// < Document field with following exclamation
+///< Document field with following exclamation
 pub const B_VAR_E: B = 4;
 /// Document field with preceeding star, with a loong long multiline
 /// comment.

tests/expectations/tests/layout_align.rs

@@ -1,6 +1,11 @@
 /* automatically generated by rust-bindgen */
 
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 #[repr(C)]
 #[derive(Copy, Clone, Debug, Default, Eq, Hash, Ord, PartialEq, PartialOrd)]
@@ -140,15 +145,15 @@ impl<T> ::std::marker::Copy for __IncompleteArrayField<T> {}
 #[repr(C)]
 #[derive(Debug)]
 pub struct rte_kni_fifo {
-    /// < Next position to be written
+    ///< Next position to be written
     pub write: ::std::os::raw::c_uint,
-    /// < Next position to be read
+    ///< Next position to be read
     pub read: ::std::os::raw::c_uint,
-    /// < Circular buffer length
+    ///< Circular buffer length
     pub len: ::std::os::raw::c_uint,
-    /// < Pointer size - for 32/64 bit OS
+    ///< Pointer size - for 32/64 bit OS
     pub elem_size: ::std::os::raw::c_uint,
-    /// < The buffer contains mbuf pointers
+    ///< The buffer contains mbuf pointers
     pub buffer: __IncompleteArrayField<*mut ::std::os::raw::c_void>,
     pub __bindgen_align: [u64; 0usize],
 }
@@ -173,7 +178,7 @@ impl Default for rte_kni_fifo {
 #[repr(C)]
 #[derive(Debug, Default, Copy, Clone)]
 pub struct rte_eth_link {
-    /// < ETH_SPEED_NUM_
+    ///< ETH_SPEED_NUM_
     pub link_speed: u32,
     pub _bitfield_1: __BindgenBitfieldUnit<[u8; 1usize], u8>,
     pub __bindgen_padding_0: [u8; 3usize],

tests/expectations/tests/layout_arp.rs

@@ -1,6 +1,11 @@
 /* automatically generated by rust-bindgen */
 
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 pub const ETHER_ADDR_LEN: u32 = 6;
 pub const ARP_HRD_ETHER: u32 = 1;
@@ -22,7 +27,7 @@ pub const ARP_OP_INVREPLY: u32 = 9;
 #[repr(C, packed)]
 #[derive(Debug, Default, Copy, Clone)]
 pub struct ether_addr {
-    /// < Addr bytes in tx order
+    ///< Addr bytes in tx order
     pub addr_bytes: [u8; 6usize],
 }
 #[test]
@@ -52,13 +57,13 @@ fn bindgen_test_layout_ether_addr() {
 #[repr(C, packed)]
 #[derive(Debug, Default, Copy, Clone)]
 pub struct arp_ipv4 {
-    /// < sender hardware address
+    ///< sender hardware address
     pub arp_sha: ether_addr,
-    /// < sender IP address
+    ///< sender IP address
     pub arp_sip: u32,
-    /// < target hardware address
+    ///< target hardware address
     pub arp_tha: ether_addr,
-    /// < target IP address
+    ///< target IP address
     pub arp_tip: u32,
 }
 #[test]

tests/expectations/tests/layout_array.rs

@@ -1,6 +1,11 @@
 /* automatically generated by rust-bindgen */
 
-#![allow(dead_code, non_snake_case, non_camel_case_types, non_upper_case_globals)]
+#![allow(
+    dead_code,
+    non_snake_case,
+    non_camel_case_types,
+    non_upper_case_globals
+)]
 
 pub const RTE_CACHE_LINE_SIZE: u32 = 64;
 pub const RTE_MEMPOOL_OPS_NAMESIZE: u32 = 32;
@@ -46,17 +51,17 @@ pub type rte_mempool_get_count =
 #[repr(C)]
 #[derive(Copy, Clone)]
 pub struct rte_mempool_ops {
-    /// < Name of mempool ops struct.
+    ///< Name of mempool ops struct.
     pub name: [::std::os::raw::c_char; 32usize],
-    /// < Allocate private data.
+    ///< Allocate private data.
     pub alloc: rte_mempool_alloc_t,
-    /// < Free the external pool.
+    ///< Free the external pool.
     pub free: rte_mempool_free_t,
-    /// < Enqueue an object.
+    ///< Enqueue an object.
     pub enqueue: rte_mempool_enqueue_t,
-    /// < Dequeue an object.
+    ///< Dequeue an object.
     pub dequeue: rte_mempool_dequeue_t,
-    /// < Get qty of available objs.
+    ///< Get qty of available objs.
     pub get_count: rte_mempool_get_count,
     pub __bindgen_padding_0: [u64; 7usize],
 }
@@ -135,16 +140,19 @@ impl Default for rte_mempool_ops {
 }
 impl ::std::cmp::PartialEq for rte_mempool_ops {
     fn eq(&self, other: &rte_mempool_ops) -> bool {
-        self.name == other.name && self.alloc == other.alloc && self.free == other.free
-            && self.enqueue == other.enqueue && self.dequeue == other.dequeue
+        self.name == other.name
+            && self.alloc == other.alloc
+            && self.free == other.free
+            && self.enqueue == other.enqueue
+            && self.dequeue == other.dequeue
             && self.get_count == other.get_count
     }
 }
 /// The rte_spinlock_t type.
 #[repr(C)]
 #[derive(Debug, Default, Copy, Clone, Hash, PartialEq, Eq)]
 pub struct rte_spinlock_t {
-    /// < lock status 0 = unlocked, 1 = locked
+    ///< lock status 0 = unlocked, 1 = locked
     pub locked: ::std::os::raw::c_int,
 }
 #[test]
@@ -180,9 +188,9 @@ fn bindgen_test_layout_rte_spinlock_t() {
 #[repr(C)]
 #[derive(Copy, Clone)]
 pub struct rte_mempool_ops_table {
-    /// < Spinlock for add/delete.
+    ///< Spinlock for add/delete.
     pub sl: rte_spinlock_t,
-    /// < Number of used ops structs in the table.
+    ///< Number of used ops structs in the table.
     pub num_ops: u32,
     pub __bindgen_padding_0: [u64; 7usize],
     /// Storage for all possible ops structs.
@@ -330,8 +338,10 @@ impl Default for malloc_heap {
 }
 impl ::std::cmp::PartialEq for malloc_heap {
     fn eq(&self, other: &malloc_heap) -> bool {
-        self.lock == other.lock && self.free_head == other.free_head
-            && self.alloc_count == other.alloc_count && self.total_size == other.total_size
+        self.lock == other.lock
+            && self.free_head == other.free_head
+            && self.alloc_count == other.alloc_count
+            && self.total_size == other.total_size
     }
 }
 #[repr(C)]