style: move postfix comments to line above

These comments should be placed on top of the line they're commenting on.
Multi-line postfix comments will no longer be aligned using rustfmt's
style edition 2024, so fix this now to prevent formatting issues later.
For consistency, single-line postfix comments are also moved.

Part of #11959

src/common.rs

@@ -849,8 +849,9 @@ pub fn read_unquoted_escape(
     let mut result_char_or_none: Option<char> = None;
 
     let mut errored = false;
-    let mut in_pos = 1; // in_pos always tracks the next character to read (and therefore the number
-                        // of characters read so far)
+    // in_pos always tracks the next character to read
+    // (and therefore the number of characters read so far)
+    let mut in_pos = 1;
 
     // For multibyte \X sequences.
     let mut byte_buff: Vec<u8> = vec![];

src/reader.rs

@@ -4373,15 +4373,20 @@ fn select_completion_in_direction(
 
 /// Restore terminal settings we care about, to prevent a broken shell.
 fn term_fix_modes(modes: &mut libc::termios) {
-    modes.c_iflag &= !ICRNL; // disable mapping CR (\cM) to NL (\cJ)
-    modes.c_iflag &= !INLCR; // disable mapping NL (\cJ) to CR (\cM)
-    modes.c_lflag &= !ICANON; // turn off canonical mode
-    modes.c_lflag &= !ECHO; // turn off echo mode
-    modes.c_lflag &= !IEXTEN; // turn off handling of discard and lnext characters
-    modes.c_oflag |= OPOST; // turn on "implementation-defined post processing" - this often
-                            // changes how line breaks work.
-    modes.c_oflag |= ONLCR; // "translate newline to carriage return-newline" - without
-                            // you see staircase output.
+    // disable mapping CR (\cM) to NL (\cJ)
+    modes.c_iflag &= !ICRNL;
+    // disable mapping NL (\cJ) to CR (\cM)
+    modes.c_iflag &= !INLCR;
+    // turn off canonical mode
+    modes.c_lflag &= !ICANON;
+    // turn off echo mode
+    modes.c_lflag &= !ECHO;
+    // turn off handling of discard and lnext characters
+    modes.c_lflag &= !IEXTEN;
+    // turn on "implementation-defined post processing" - this often changes how line breaks work.
+    modes.c_oflag |= OPOST;
+    // "translate newline to carriage return-newline" - without you see staircase output.
+    modes.c_oflag |= ONLCR;
 
     modes.c_cc[VMIN] = 1;
     modes.c_cc[VTIME] = 0;

src/tokenizer.rs

@@ -1333,8 +1333,9 @@ fn consume_char_whitespace(&mut self, c: char) -> bool {
         while self.state != S_END && !consumed {
             match self.state {
                 S_ALWAYS_ONE => {
-                    consumed = true; // always consume the first character
-                                     // If it's not whitespace, only consume those from here.
+                    // always consume the first character
+                    // If it's not whitespace, only consume those from here.
+                    consumed = true;
                     if !c.is_whitespace() {
                         self.state = S_GRAPH;
                     } else {
@@ -1344,14 +1345,16 @@ fn consume_char_whitespace(&mut self, c: char) -> bool {
                 }
                 S_BLANK => {
                     if c.is_whitespace() {
-                        consumed = true; // consumed whitespace
+                        // consumed whitespace
+                        consumed = true;
                     } else {
                         self.state = S_GRAPH;
                     }
                 }
                 S_GRAPH => {
                     if !c.is_whitespace() {
-                        consumed = true; // consumed printable non-space
+                        // consumed printable non-space
+                        consumed = true;
                     } else {
                         self.state = S_END;
                     }