scanner/stats: move MStats into its own module

and update the various use statements, plus better documentation on the
fields / methods

src/scanner/key.rs

@@ -66,7 +66,7 @@
 //! queue position
 //! ```
 
-use super::MStats;
+use crate::scanner::stats::MStats;
 
 /// Manages the state for tracking possible implicit Keys
 /// that the Scanner might may encounter during runtime

src/scanner/mod.rs

@@ -8,10 +8,9 @@ mod entry;
 mod error;
 mod key;
 mod scalar;
+mod stats;
 mod tag;
 
-use std::ops::{Add, AddAssign};
-
 use atoi::atoi;
 
 use self::{
@@ -20,6 +19,7 @@ use self::{
     error::{ScanError, ScanResult as Result},
     key::{Key, KeyPossible},
     scalar::{block::scan_block_scalar, plain::scan_plain_scalar},
+    stats::MStats,
 };
 use crate::{
     queue::Queue,
@@ -1224,77 +1224,6 @@ fn is_plain_safe_c(base: &str, offset: usize, block_context: bool) -> bool
     block_context || (flow_context && not_flow_indicator)
 }
 
-/// Vessel for tracking various stats about the underlying
-/// buffer that are required for correct parsing of certain
-/// elements, and when contextualizing an error.
-#[derive(Debug, Clone, PartialEq)]
-struct MStats
-{
-    read:   usize,
-    lines:  usize,
-    column: usize,
-}
-
-impl MStats
-{
-    fn new() -> Self
-    {
-        Self::default()
-    }
-
-    fn update(&mut self, read: usize, lines: usize, column: usize)
-    {
-        self.read += read;
-        self.lines += lines;
-
-        match lines
-        {
-            0 => self.column += column,
-            _ => self.column = column,
-        }
-    }
-}
-
-impl Default for MStats
-{
-    fn default() -> Self
-    {
-        Self {
-            read:   0,
-            lines:  0,
-            column: 0,
-        }
-    }
-}
-
-impl Add for MStats
-{
-    type Output = Self;
-
-    fn add(mut self, rhs: Self) -> Self::Output
-    {
-        self += rhs;
-
-        self
-    }
-}
-
-impl AddAssign for MStats
-{
-    fn add_assign(&mut self, rhs: Self)
-    {
-        self.update(rhs.read, rhs.lines, rhs.column)
-    }
-}
-
-impl PartialEq<(usize, usize, usize)> for MStats
-{
-    fn eq(&self, (read, lines, column): &(usize, usize, usize)) -> bool
-    {
-        self.read == *read && self.lines == *lines && self.column == *column
-    }
-}
-
 const DIRECTIVE: u8 = b'%';
 const ANCHOR: u8 = b'&';
 const ALIAS: u8 = b'*';

src/scanner/scalar/block.rs

@@ -26,7 +26,7 @@ use crate::{
     scanner::{
         context::Context,
         error::{ScanError, ScanResult as Result},
-        MStats,
+        stats::MStats,
     },
     token::{ScalarStyle, Slice, Token},
 };

src/scanner/scalar/flow.rs

@@ -4,7 +4,7 @@ use crate::{
     scanner::{
         error::{ScanError, ScanResult as Result},
         scalar::escape::flow_unescape,
-        MStats,
+        stats::MStats,
     },
     token::{ScalarStyle, Token},
 };

src/scanner/scalar/plain.rs

@@ -2,7 +2,7 @@ use crate::{
     scanner::{
         context::Context,
         error::{ScanError, ScanResult as Result},
-        MStats,
+        stats::MStats,
     },
     token::{ScalarStyle, Token},
 };

src/scanner/stats.rs

@@ -0,0 +1,85 @@
+//! Contains the structure used for tracking marker stats in
+//! a buffer, namely:
+//!
+//! - How far into the buffer have we read?
+//! - How many lines have we read?
+//! - What is the current column?
+
+use std::ops::{Add, AddAssign};
+
+/// Vessel for tracking various stats about the underlying
+/// buffer that are required for correct parsing of certain
+/// elements, and when contextualizing an error.
+#[derive(Debug, Clone, PartialEq)]
+pub(in crate::scanner) struct MStats
+{
+    /// Amount of bytes read from the underlying byte stream
+    pub read:   usize,
+    /// Number of lines seen in the underlying byte stream
+    pub lines:  usize,
+    /// The offset from the last line break into a line
+    pub column: usize,
+}
+
+impl MStats
+{
+    /// Construct a new empty MStats instance
+    pub fn new() -> Self
+    {
+        Self::default()
+    }
+
+    /// Update the stored stats with the given .read .lines
+    /// and .column
+    pub fn update(&mut self, read: usize, lines: usize, column: usize)
+    {
+        self.read += read;
+        self.lines += lines;
+
+        match lines
+        {
+            0 => self.column += column,
+            _ => self.column = column,
+        }
+    }
+}
+
+impl Default for MStats
+{
+    fn default() -> Self
+    {
+        Self {
+            read:   0,
+            lines:  0,
+            column: 0,
+        }
+    }
+}
+
+impl Add for MStats
+{
+    type Output = Self;
+
+    fn add(mut self, rhs: Self) -> Self::Output
+    {
+        self += rhs;
+
+        self
+    }
+}
+
+impl AddAssign for MStats
+{
+    fn add_assign(&mut self, rhs: Self)
+    {
+        self.update(rhs.read, rhs.lines, rhs.column)
+    }
+}
+
+impl PartialEq<(usize, usize, usize)> for MStats
+{
+    fn eq(&self, (read, lines, column): &(usize, usize, usize)) -> bool
+    {
+        self.read == *read && self.lines == *lines && self.column == *column
+    }
+}

src/scanner/tag.rs

@@ -67,7 +67,7 @@ use crate::{
         eat_whitespace,
         error::{ScanError, ScanResult as Result},
         scalar::escape::tag_uri_unescape,
-        MStats,
+        stats::MStats,
     },
     token::{Slice, Token},
 };