Replace format flags u32 by enums and bools.

6 files changed, 154 insertions, 62 deletions

diff --git a/compiler/rustc_ast/src/format.rs b/compiler/rustc_ast/src/format.rs
index da05b09b37d..d021bea5eca 100644
--- a/compiler/rustc_ast/src/format.rs
+++ b/compiler/rustc_ast/src/format.rs
@@ -227,8 +227,30 @@ pub struct FormatOptions {
     pub alignment: Option<FormatAlignment>,
     /// The fill character. E.g. the `.` in `{:.>10}`.
     pub fill: Option<char>,
-    /// The `+`, `-`, `0`, `#`, `x?` and `X?` flags.
-    pub flags: u32,
+    /// The `+` or `-` flag.
+    pub sign: Option<FormatSign>,
+    /// The `#` flag.
+    pub alternate: bool,
+    /// The `0` flag. E.g. the `0` in `{:02x}`.
+    pub zero_pad: bool,
+    /// The `x` or `X` flag (for `Debug` only). E.g. the `x` in `{:x?}`.
+    pub debug_hex: Option<FormatDebugHex>,
+}
+
+#[derive(Copy, Clone, Encodable, Decodable, Debug, PartialEq, Eq)]
+pub enum FormatSign {
+    /// The `+` flag.
+    Plus,
+    /// The `-` flag.
+    Minus,
+}
+
+#[derive(Copy, Clone, Encodable, Decodable, Debug, PartialEq, Eq)]
+pub enum FormatDebugHex {
+    /// The `x` flag in `{:x?}`.
+    Lower,
+    /// The `X` flag in `{:X?}`.
+    Upper,
 }
 
 #[derive(Copy, Clone, Encodable, Decodable, Debug, PartialEq, Eq)]
diff --git a/compiler/rustc_ast_lowering/src/format.rs b/compiler/rustc_ast_lowering/src/format.rs
index 776b532b0de..5d1770c734d 100644
--- a/compiler/rustc_ast_lowering/src/format.rs
+++ b/compiler/rustc_ast_lowering/src/format.rs
@@ -148,7 +148,14 @@ fn make_format_spec<'hir>(
             None => sym::Unknown,
         },
     );
-    let flags = ctx.expr_u32(sp, placeholder.format_options.flags);
+    // This needs to match `FlagV1` in library/core/src/fmt/mod.rs.
+    let flags: u32 = ((placeholder.format_options.sign == Some(FormatSign::Plus)) as u32)
+        | ((placeholder.format_options.sign == Some(FormatSign::Minus)) as u32) << 1
+        | (placeholder.format_options.alternate as u32) << 2
+        | (placeholder.format_options.zero_pad as u32) << 3
+        | ((placeholder.format_options.debug_hex == Some(FormatDebugHex::Lower)) as u32) << 4
+        | ((placeholder.format_options.debug_hex == Some(FormatDebugHex::Upper)) as u32) << 5;
+    let flags = ctx.expr_u32(sp, flags);
     let prec = make_count(ctx, sp, &placeholder.format_options.precision, argmap);
     let width = make_count(ctx, sp, &placeholder.format_options.width, argmap);
     let format_placeholder_new = ctx.arena.alloc(ctx.expr_lang_item_type_relative(
diff --git a/compiler/rustc_ast_pretty/src/pprust/state/expr.rs b/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
index 99ffa19016f..cacfe9eb2f1 100644
--- a/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
@@ -6,7 +6,10 @@ use rustc_ast::token;
 use rustc_ast::util::literal::escape_byte_str_symbol;
 use rustc_ast::util::parser::{self, AssocOp, Fixity};
 use rustc_ast::{self as ast, BlockCheckMode};
-use rustc_ast::{FormatAlignment, FormatArgPosition, FormatArgsPiece, FormatCount, FormatTrait};
+use rustc_ast::{
+    FormatAlignment, FormatArgPosition, FormatArgsPiece, FormatCount, FormatDebugHex, FormatSign,
+    FormatTrait,
+};
 use std::fmt::Write;
 
 impl<'a> State<'a> {
@@ -675,17 +678,15 @@ pub fn reconstruct_format_args_template_string(pieces: &[FormatArgsPiece]) -> St
                     Some(FormatAlignment::Center) => template.push_str("^"),
                     None => {}
                 }
-                let flags = p.format_options.flags;
-                if flags >> (rustc_parse_format::FlagSignPlus as usize) & 1 != 0 {
-                    template.push('+');
-                }
-                if flags >> (rustc_parse_format::FlagSignMinus as usize) & 1 != 0 {
-                    template.push('-');
+                match p.format_options.sign {
+                    Some(FormatSign::Plus) => template.push('+'),
+                    Some(FormatSign::Minus) => template.push('-'),
+                    None => {}
                 }
-                if flags >> (rustc_parse_format::FlagAlternate as usize) & 1 != 0 {
+                if p.format_options.alternate {
                     template.push('#');
                 }
-                if flags >> (rustc_parse_format::FlagSignAwareZeroPad as usize) & 1 != 0 {
+                if p.format_options.zero_pad {
                     template.push('0');
                 }
                 if let Some(width) = &p.format_options.width {
@@ -709,11 +710,10 @@ pub fn reconstruct_format_args_template_string(pieces: &[FormatArgsPiece]) -> St
                         }
                     }
                 }
-                if flags >> (rustc_parse_format::FlagDebugLowerHex as usize) & 1 != 0 {
-                    template.push('x');
-                }
-                if flags >> (rustc_parse_format::FlagDebugUpperHex as usize) & 1 != 0 {
-                    template.push('X');
+                match p.format_options.debug_hex {
+                    Some(FormatDebugHex::Lower) => template.push('x'),
+                    Some(FormatDebugHex::Upper) => template.push('X'),
+                    None => {}
                 }
                 template.push_str(match p.format_trait {
                     FormatTrait::Display => "",
diff --git a/compiler/rustc_builtin_macros/src/format.rs b/compiler/rustc_builtin_macros/src/format.rs
index 469f0dc1303..e93a23394c0 100644
--- a/compiler/rustc_builtin_macros/src/format.rs
+++ b/compiler/rustc_builtin_macros/src/format.rs
@@ -4,7 +4,7 @@ use rustc_ast::tokenstream::TokenStream;
 use rustc_ast::{
     Expr, ExprKind, FormatAlignment, FormatArgPosition, FormatArgPositionKind, FormatArgs,
     FormatArgsPiece, FormatArgument, FormatArgumentKind, FormatArguments, FormatCount,
-    FormatOptions, FormatPlaceholder, FormatTrait,
+    FormatDebugHex, FormatOptions, FormatPlaceholder, FormatSign, FormatTrait,
 };
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::{pluralize, Applicability, MultiSpan, PResult};
@@ -435,7 +435,16 @@ pub fn make_format_args(
                     format_options: FormatOptions {
                         fill: format.fill,
                         alignment,
-                        flags: format.flags,
+                        sign: format.sign.map(|s| match s {
+                            parse::Sign::Plus => FormatSign::Plus,
+                            parse::Sign::Minus => FormatSign::Minus,
+                        }),
+                        alternate: format.alternate,
+                        zero_pad: format.zero_pad,
+                        debug_hex: format.debug_hex.map(|s| match s {
+                            parse::DebugHex::Lower => FormatDebugHex::Lower,
+                            parse::DebugHex::Upper => FormatDebugHex::Upper,
+                        }),
                         precision,
                         width,
                     },
diff --git a/compiler/rustc_parse_format/src/lib.rs b/compiler/rustc_parse_format/src/lib.rs
index 7b016cadac3..a6dfcd29762 100644
--- a/compiler/rustc_parse_format/src/lib.rs
+++ b/compiler/rustc_parse_format/src/lib.rs
@@ -16,7 +16,6 @@
 
 pub use Alignment::*;
 pub use Count::*;
-pub use Flag::*;
 pub use Piece::*;
 pub use Position::*;
 
@@ -111,8 +110,14 @@ pub struct FormatSpec<'a> {
     pub fill: Option<char>,
     /// Optionally specified alignment.
     pub align: Alignment,
-    /// Packed version of various flags provided.
-    pub flags: u32,
+    /// The `+` or `-` flag.
+    pub sign: Option<Sign>,
+    /// The `#` flag.
+    pub alternate: bool,
+    /// The `0` flag.
+    pub zero_pad: bool,
+    /// The `x` or `X` flag. (Only for `Debug`.)
+    pub debug_hex: Option<DebugHex>,
     /// The integer precision to use.
     pub precision: Count<'a>,
     /// The span of the precision formatting flag (for diagnostics).
@@ -162,24 +167,22 @@ pub enum Alignment {
     AlignUnknown,
 }
 
-/// Various flags which can be applied to format strings. The meaning of these
-/// flags is defined by the formatters themselves.
+/// Enum for the sign flags.
 #[derive(Copy, Clone, Debug, PartialEq)]
-pub enum Flag {
-    /// A `+` will be used to denote positive numbers.
-    FlagSignPlus,
-    /// A `-` will be used to denote negative numbers. This is the default.
-    FlagSignMinus,
-    /// An alternate form will be used for the value. In the case of numbers,
-    /// this means that the number will be prefixed with the supplied string.
-    FlagAlternate,
-    /// For numbers, this means that the number will be padded with zeroes,
-    /// and the sign (`+` or `-`) will precede them.
-    FlagSignAwareZeroPad,
-    /// For Debug / `?`, format integers in lower-case hexadecimal.
-    FlagDebugLowerHex,
-    /// For Debug / `?`, format integers in upper-case hexadecimal.
-    FlagDebugUpperHex,
+pub enum Sign {
+    /// The `+` flag.
+    Plus,
+    /// The `-` flag.
+    Minus,
+}
+
+/// Enum for the debug hex flags.
+#[derive(Copy, Clone, Debug, PartialEq)]
+pub enum DebugHex {
+    /// The `x` flag in `{:x?}`.
+    Lower,
+    /// The `X` flag in `{:X?}`.
+    Upper,
 }
 
 /// A count is used for the precision and width parameters of an integer, and
@@ -597,7 +600,10 @@ impl<'a> Parser<'a> {
         let mut spec = FormatSpec {
             fill: None,
             align: AlignUnknown,
-            flags: 0,
+            sign: None,
+            alternate: false,
+            zero_pad: false,
+            debug_hex: None,
             precision: CountImplied,
             precision_span: None,
             width: CountImplied,
@@ -626,13 +632,13 @@ impl<'a> Parser<'a> {
         }
         // Sign flags
         if self.consume('+') {
-            spec.flags |= 1 << (FlagSignPlus as u32);
+            spec.sign = Some(Sign::Plus);
         } else if self.consume('-') {
-            spec.flags |= 1 << (FlagSignMinus as u32);
+            spec.sign = Some(Sign::Minus);
         }
         // Alternate marker
         if self.consume('#') {
-            spec.flags |= 1 << (FlagAlternate as u32);
+            spec.alternate = true;
         }
         // Width and precision
         let mut havewidth = false;
@@ -647,7 +653,7 @@ impl<'a> Parser<'a> {
                 spec.width_span = Some(self.span(end - 1, end + 1));
                 havewidth = true;
             } else {
-                spec.flags |= 1 << (FlagSignAwareZeroPad as u32);
+                spec.zero_pad = true;
             }
         }
 
@@ -678,14 +684,14 @@ impl<'a> Parser<'a> {
         // Optional radix followed by the actual format specifier
         if self.consume('x') {
             if self.consume('?') {
-                spec.flags |= 1 << (FlagDebugLowerHex as u32);
+                spec.debug_hex = Some(DebugHex::Lower);
                 spec.ty = "?";
             } else {
                 spec.ty = "x";
             }
         } else if self.consume('X') {
             if self.consume('?') {
-                spec.flags |= 1 << (FlagDebugUpperHex as u32);
+                spec.debug_hex = Some(DebugHex::Upper);
                 spec.ty = "?";
             } else {
                 spec.ty = "X";
@@ -708,7 +714,10 @@ impl<'a> Parser<'a> {
         let mut spec = FormatSpec {
             fill: None,
             align: AlignUnknown,
-            flags: 0,
+            sign: None,
+            alternate: false,
+            zero_pad: false,
+            debug_hex: None,
             precision: CountImplied,
             precision_span: None,
             width: CountImplied,
diff --git a/compiler/rustc_parse_format/src/tests.rs b/compiler/rustc_parse_format/src/tests.rs
index 2992ba845ab..45314e2fb55 100644
--- a/compiler/rustc_parse_format/src/tests.rs
+++ b/compiler/rustc_parse_format/src/tests.rs
@@ -10,7 +10,10 @@ fn fmtdflt() -> FormatSpec<'static> {
     return FormatSpec {
         fill: None,
         align: AlignUnknown,
-        flags: 0,
+        sign: None,
+        alternate: false,
+        zero_pad: false,
+        debug_hex: None,
         precision: CountImplied,
         width: CountImplied,
         precision_span: None,
@@ -126,7 +129,10 @@ fn format_type() {
             format: FormatSpec {
                 fill: None,
                 align: AlignUnknown,
-                flags: 0,
+                sign: None,
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountImplied,
                 width: CountImplied,
                 precision_span: None,
@@ -147,7 +153,10 @@ fn format_align_fill() {
             format: FormatSpec {
                 fill: None,
                 align: AlignRight,
-                flags: 0,
+                sign: None,
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountImplied,
                 width: CountImplied,
                 precision_span: None,
@@ -165,7 +174,10 @@ fn format_align_fill() {
             format: FormatSpec {
                 fill: Some('0'),
                 align: AlignLeft,
-                flags: 0,
+                sign: None,
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountImplied,
                 width: CountImplied,
                 precision_span: None,
@@ -183,7 +195,10 @@ fn format_align_fill() {
             format: FormatSpec {
                 fill: Some('*'),
                 align: AlignLeft,
-                flags: 0,
+                sign: None,
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountImplied,
                 width: CountImplied,
                 precision_span: None,
@@ -204,7 +219,10 @@ fn format_counts() {
             format: FormatSpec {
                 fill: None,
                 align: AlignUnknown,
-                flags: 0,
+                sign: None,
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountImplied,
                 precision_span: None,
                 width: CountIs(10),
@@ -222,7 +240,10 @@ fn format_counts() {
             format: FormatSpec {
                 fill: None,
                 align: AlignUnknown,
-                flags: 0,
+                sign: None,
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountIs(10),
                 precision_span: Some(InnerSpan { start: 6, end: 9 }),
                 width: CountIsParam(10),
@@ -240,7 +261,10 @@ fn format_counts() {
             format: FormatSpec {
                 fill: None,
                 align: AlignUnknown,
-                flags: 0,
+                sign: None,
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountIs(10),
                 precision_span: Some(InnerSpan { start: 6, end: 9 }),
                 width: CountIsParam(0),
@@ -258,7 +282,10 @@ fn format_counts() {
             format: FormatSpec {
                 fill: None,
                 align: AlignUnknown,
-                flags: 0,
+                sign: None,
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountIsStar(0),
                 precision_span: Some(InnerSpan { start: 3, end: 5 }),
                 width: CountImplied,
@@ -276,7 +303,10 @@ fn format_counts() {
             format: FormatSpec {
                 fill: None,
                 align: AlignUnknown,
-                flags: 0,
+                sign: None,
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountIsParam(10),
                 width: CountImplied,
                 precision_span: Some(InnerSpan::new(3, 7)),
@@ -294,7 +324,10 @@ fn format_counts() {
             format: FormatSpec {
                 fill: None,
                 align: AlignUnknown,
-                flags: 0,
+                sign: None,
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountIsName("b", InnerSpan { start: 6, end: 7 }),
                 precision_span: Some(InnerSpan { start: 5, end: 8 }),
                 width: CountIsName("a", InnerSpan { start: 3, end: 4 }),
@@ -312,7 +345,10 @@ fn format_counts() {
             format: FormatSpec {
                 fill: None,
                 align: AlignUnknown,
-                flags: 0,
+                sign: None,
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountIs(4),
                 precision_span: Some(InnerSpan { start: 3, end: 5 }),
                 width: CountImplied,
@@ -333,7 +369,10 @@ fn format_flags() {
             format: FormatSpec {
                 fill: None,
                 align: AlignUnknown,
-                flags: (1 << FlagSignMinus as u32),
+                sign: Some(Sign::Minus),
+                alternate: false,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountImplied,
                 width: CountImplied,
                 precision_span: None,
@@ -351,7 +390,10 @@ fn format_flags() {
             format: FormatSpec {
                 fill: None,
                 align: AlignUnknown,
-                flags: (1 << FlagSignPlus as u32) | (1 << FlagAlternate as u32),
+                sign: Some(Sign::Plus),
+                alternate: true,
+                zero_pad: false,
+                debug_hex: None,
                 precision: CountImplied,
                 width: CountImplied,
                 precision_span: None,
@@ -374,7 +416,10 @@ fn format_mixture() {
                 format: FormatSpec {
                     fill: None,
                     align: AlignUnknown,
-                    flags: 0,
+                    sign: None,
+                    alternate: false,
+                    zero_pad: false,
+                    debug_hex: None,
                     precision: CountImplied,
                     width: CountImplied,
                     precision_span: None,