Add QoL conversion methods and explicit 0s to TextWidth and TextOffset (

#7036)

crates/cairo-lang-defs/src/patcher.rs

@@ -268,13 +268,8 @@ impl<'a> PatchBuilder<'a> {
     /// Builds the resulting code and code mappings.
     pub fn build(mut self) -> (String, Vec<CodeMapping>) {
         // Adds the mapping to the original node from all code not previously mapped.
-        self.code_mappings.push(CodeMapping {
-            span: TextSpan {
-                start: TextOffset::default(),
-                end: TextOffset::default().add_width(TextWidth::from_str(&self.code)),
-            },
-            origin: self.origin,
-        });
+        self.code_mappings
+            .push(CodeMapping { span: TextSpan::from_str(&self.code), origin: self.origin });
         (self.code, self.code_mappings)
     }
 
@@ -320,7 +315,7 @@ impl<'a> PatchBuilder<'a> {
     }
 
     pub fn add_node(&mut self, node: SyntaxNode) {
-        let start = TextOffset::default().add_width(TextWidth::from_str(&self.code));
+        let start = TextOffset::from_str(&self.code);
         let orig_span = node.span(self.db);
         self.code_mappings.push(CodeMapping {
             span: TextSpan { start, end: start.add_width(orig_span.width()) },
@@ -330,9 +325,9 @@ impl<'a> PatchBuilder<'a> {
     }
 
     fn add_mapped(&mut self, node: RewriteNode, origin: TextSpan) {
-        let start = TextOffset::default().add_width(TextWidth::from_str(&self.code));
+        let start = TextOffset::from_str(&self.code);
         self.add_modified(node);
-        let end = TextOffset::default().add_width(TextWidth::from_str(&self.code));
+        let end = TextOffset::from_str(&self.code);
         self.code_mappings
             .push(CodeMapping { span: TextSpan { start, end }, origin: CodeOrigin::Span(origin) });
     }
@@ -344,7 +339,7 @@ impl<'a> PatchBuilder<'a> {
         let origin_span = TextSpan { start: orig_start, end: orig_end };
 
         let text = node.get_text_of_span(self.db, origin_span);
-        let start = TextOffset::default().add_width(TextWidth::from_str(&self.code));
+        let start = TextOffset::from_str(&self.code);
 
         self.code += &text;
 

crates/cairo-lang-diagnostics/src/diagnostics_test.rs

@@ -24,8 +24,8 @@ impl DiagnosticEntry for SimpleDiag {
         DiagnosticLocation {
             file_id: self.file_id,
             span: TextSpan {
-                start: TextOffset::default().add_width(TextWidth::new_for_testing(0)),
-                end: TextOffset::default().add_width(TextWidth::new_for_testing(6)),
+                start: TextOffset::START,
+                end: TextWidth::new_for_testing(6).as_offset(),
             },
         }
     }

crates/cairo-lang-filesystem/src/db.rs

@@ -334,8 +334,8 @@ fn file_content(db: &dyn FilesGroup, file: FileId) -> Option<Arc<str>> {
 }
 fn file_summary(db: &dyn FilesGroup, file: FileId) -> Option<Arc<FileSummary>> {
     let content = db.file_content(file)?;
-    let mut line_offsets = vec![TextOffset::default()];
-    let mut offset = TextOffset::default();
+    let mut line_offsets = vec![TextOffset::START];
+    let mut offset = TextOffset::START;
     for ch in content.chars() {
         offset = offset.add_width(TextWidth::from_char(ch));
         if ch == '\n' {

crates/cairo-lang-filesystem/src/span.rs

@@ -17,6 +17,8 @@ mod test;
 )]
 pub struct TextWidth(u32);
 impl TextWidth {
+    pub const ZERO: Self = Self(0);
+
     pub fn from_char(c: char) -> Self {
         Self(c.len_utf8() as u32)
     }
@@ -27,9 +29,24 @@ impl TextWidth {
     pub fn new_for_testing(value: u32) -> Self {
         Self(value)
     }
+    /// Creates a `TextWidth` at the given index of a string.
+    ///
+    /// The index is required to be a char boundary.
+    /// This function runs a debug assertion to verify this,
+    /// while retains performance on release builds.
+    pub fn at(s: &str, index: usize) -> Self {
+        debug_assert!(
+            s.is_char_boundary(index),
+            "cannot create a TextWidth outside of a char boundary"
+        );
+        Self(index as u32)
+    }
     pub fn as_u32(self) -> u32 {
         self.0
     }
+    pub fn as_offset(self) -> TextOffset {
+        TextOffset(self)
+    }
 }
 impl Add for TextWidth {
     type Output = Self;
@@ -57,6 +74,13 @@ impl Sum for TextWidth {
 )]
 pub struct TextOffset(TextWidth);
 impl TextOffset {
+    pub const START: Self = Self(TextWidth::ZERO);
+
+    /// Creates a `TextOffset` at the end of a given string.
+    #[allow(clippy::should_implement_trait)]
+    pub fn from_str(content: &str) -> Self {
+        Self(TextWidth::from_str(content))
+    }
     pub fn add_width(self, width: TextWidth) -> Self {
         TextOffset(self.0 + width)
     }
@@ -87,6 +111,11 @@ pub struct TextSpan {
     pub end: TextOffset,
 }
 impl TextSpan {
+    /// Creates a `TextSpan` for the entirety of a given string.
+    #[allow(clippy::should_implement_trait)]
+    pub fn from_str(content: &str) -> Self {
+        Self { start: TextOffset::START, end: TextOffset::from_str(content) }
+    }
     pub fn width(self) -> TextWidth {
         self.end - self.start
     }

crates/cairo-lang-parser/src/db_test.rs

@@ -1,15 +1,14 @@
 use std::path::PathBuf;
 
 use cairo_lang_filesystem::ids::FileId;
-use cairo_lang_filesystem::span::{TextOffset, TextSpan, TextWidth};
+use cairo_lang_filesystem::span::TextSpan;
 use cairo_lang_syntax::node::ast::{
     ModuleItemList, SyntaxFile, TerminalEndOfFile, TokenEndOfFile, Trivia,
 };
 use cairo_lang_syntax::node::db::SyntaxGroup;
 use cairo_lang_syntax::node::{SyntaxNode, Terminal, Token as SyntaxToken, TypedSyntaxNode};
 use cairo_lang_utils::Upcast;
 use indoc::indoc;
-use num_traits::ToPrimitive;
 use pretty_assertions::assert_eq;
 use smol_str::SmolStr;
 use test_log::test;
@@ -96,11 +95,7 @@ fn test_token_stream_expr_parser() {
     let token_stream = MockTokenStream {
         tokens: vec![MockToken {
             content: expr_code.to_string(),
-            span: TextSpan {
-                start: TextOffset::default(),
-                end: TextOffset::default()
-                    .add_width(TextWidth::new_for_testing(expr_code.len().to_u32().unwrap())),
-            },
+            span: TextSpan::from_str(expr_code),
         }],
         content_string: expr_code.to_string(),
     };

crates/cairo-lang-parser/src/lexer.rs

@@ -27,8 +27,8 @@ impl<'a> Lexer<'a> {
         Lexer {
             db,
             text,
-            previous_position: TextOffset::default(),
-            current_position: TextOffset::default(),
+            previous_position: TextOffset::START,
+            current_position: TextOffset::START,
             done: false,
         }
     }

crates/cairo-lang-plugins/src/test.rs

@@ -14,7 +14,7 @@ use cairo_lang_filesystem::db::{
 use cairo_lang_filesystem::ids::{
     CodeMapping, CodeOrigin, CrateId, Directory, FileLongId, VirtualFile,
 };
-use cairo_lang_filesystem::span::{TextOffset, TextSpan, TextWidth};
+use cairo_lang_filesystem::span::TextSpan;
 use cairo_lang_parser::db::ParserDatabase;
 use cairo_lang_syntax::node::db::{SyntaxDatabase, SyntaxGroup};
 use cairo_lang_syntax::node::helpers::QueryAttrs;
@@ -160,10 +160,7 @@ impl MacroPlugin for DoubleIndirectionPlugin {
         let orig_span = node.span(db);
         let code_mappings = |content: &str| {
             vec![CodeMapping {
-                span: TextSpan {
-                    start: TextOffset::default(),
-                    end: TextOffset::default().add_width(TextWidth::from_str(content)),
-                },
+                span: TextSpan::from_str(content),
                 origin: CodeOrigin::Start(orig_span.start),
             }]
         };

crates/cairo-lang-semantic/src/inline_macros/consteval_int.rs

@@ -4,7 +4,7 @@ use cairo_lang_defs::plugin::{
     PluginGeneratedFile,
 };
 use cairo_lang_filesystem::ids::{CodeMapping, CodeOrigin};
-use cairo_lang_filesystem::span::{TextOffset, TextSpan, TextWidth};
+use cairo_lang_filesystem::span::TextSpan;
 use cairo_lang_syntax::node::db::SyntaxGroup;
 use cairo_lang_syntax::node::{TypedStablePtr, TypedSyntaxNode, ast};
 use indoc::indoc;
@@ -45,10 +45,7 @@ impl InlineMacroExprPlugin for ConstevalIntMacro {
         InlinePluginResult {
             code: code.map(|x| {
                 let content = x.to_string();
-                let span = TextSpan {
-                    start: TextOffset::default(),
-                    end: TextOffset::default().add_width(TextWidth::from_str(&content)),
-                };
+                let span = TextSpan::from_str(&content);
                 PluginGeneratedFile {
                     name: "consteval_int_inline_macro".into(),
                     content,

crates/cairo-lang-starknet/src/plugin/test.rs

@@ -7,7 +7,7 @@ use cairo_lang_defs::ids::ModuleId;
 use cairo_lang_diagnostics::DiagnosticLocation;
 use cairo_lang_filesystem::db::FilesGroup;
 use cairo_lang_filesystem::ids::FileLongId;
-use cairo_lang_filesystem::span::{TextOffset, TextSpan, TextWidth};
+use cairo_lang_filesystem::span::TextSpan;
 use cairo_lang_plugins::test_utils::expand_module_text;
 use cairo_lang_semantic::test_utils::setup_test_module;
 use cairo_lang_test_utils::parse_test_file::{TestFileRunner, TestRunnerResult};
@@ -49,9 +49,8 @@ impl TestFileRunner for ExpandContractTestRunner {
 
         for file_id in files {
             let content = db.file_content(file_id).unwrap();
-            let start = TextOffset::default();
-            let end = start.add_width(TextWidth::from_str(&content));
-            let content_location = DiagnosticLocation { file_id, span: TextSpan { start, end } };
+            let content_location =
+                DiagnosticLocation { file_id, span: TextSpan::from_str(&content) };
             let original_location = content_location.user_location(db.upcast());
             let origin = (content_location != original_location)
                 .then(|| format!("{:?}\n", original_location.debug(db.upcast())))

crates/cairo-lang-syntax/src/node/ast_test.rs

@@ -26,106 +26,86 @@ fn test_ast() {
             .map(|node| (node.kind(db), node.text(db), node.offset(), node.width(db)))
             .collect::<Vec<_>>(),
         vec![
-            (
-                SyntaxKind::ExprBinary,
-                None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(0)),
-                TextWidth::new_for_testing(7)
-            ),
-            (
-                SyntaxKind::ExprPath,
-                None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(0)),
-                TextWidth::new_for_testing(4)
-            ),
-            (
-                SyntaxKind::PathSegmentSimple,
-                None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(0)),
-                TextWidth::new_for_testing(4)
-            ),
+            (SyntaxKind::ExprBinary, None, TextOffset::START, TextWidth::new_for_testing(7)),
+            (SyntaxKind::ExprPath, None, TextOffset::START, TextWidth::new_for_testing(4)),
+            (SyntaxKind::PathSegmentSimple, None, TextOffset::START, TextWidth::new_for_testing(4)),
             (
                 SyntaxKind::TerminalIdentifier,
                 None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(0)),
+                TextOffset::START,
                 TextWidth::new_for_testing(4)
             ),
-            (
-                SyntaxKind::Trivia,
-                None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(0)),
-                TextWidth::new_for_testing(0)
-            ),
+            (SyntaxKind::Trivia, None, TextOffset::START, TextWidth::new_for_testing(0)),
             (
                 SyntaxKind::TokenIdentifier,
                 Some("foo".into()),
-                TextOffset::default().add_width(TextWidth::new_for_testing(0)),
+                TextOffset::START,
                 TextWidth::new_for_testing(3)
             ),
             (
                 SyntaxKind::Trivia,
                 None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(3)),
+                TextWidth::new_for_testing(3).as_offset(),
                 TextWidth::new_for_testing(1)
             ),
             (
                 SyntaxKind::TokenWhitespace,
                 Some(" ".into()),
-                TextOffset::default().add_width(TextWidth::new_for_testing(3)),
+                TextWidth::new_for_testing(3).as_offset(),
                 TextWidth::new_for_testing(1)
             ),
             (
                 SyntaxKind::TerminalPlus,
                 None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(4)),
+                TextWidth::new_for_testing(4).as_offset(),
                 TextWidth::new_for_testing(2)
             ),
             (
                 SyntaxKind::Trivia,
                 None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(4)),
+                TextWidth::new_for_testing(4).as_offset(),
                 TextWidth::new_for_testing(0)
             ),
             (
                 SyntaxKind::TokenPlus,
                 Some("+".into()),
-                TextOffset::default().add_width(TextWidth::new_for_testing(4)),
+                TextWidth::new_for_testing(4).as_offset(),
                 TextWidth::new_for_testing(1)
             ),
             (
                 SyntaxKind::Trivia,
                 None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(5)),
+                TextWidth::new_for_testing(5).as_offset(),
                 TextWidth::new_for_testing(1)
             ),
             (
                 SyntaxKind::TokenWhitespace,
                 Some(" ".into()),
-                TextOffset::default().add_width(TextWidth::new_for_testing(5)),
+                TextWidth::new_for_testing(5).as_offset(),
                 TextWidth::new_for_testing(1)
             ),
             (
                 SyntaxKind::TerminalLiteralNumber,
                 None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(6)),
+                TextWidth::new_for_testing(6).as_offset(),
                 TextWidth::new_for_testing(1)
             ),
             (
                 SyntaxKind::Trivia,
                 None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(6)),
+                TextWidth::new_for_testing(6).as_offset(),
                 TextWidth::new_for_testing(0)
             ),
             (
                 SyntaxKind::TokenLiteralNumber,
                 Some("5".into()),
-                TextOffset::default().add_width(TextWidth::new_for_testing(6)),
+                TextWidth::new_for_testing(6).as_offset(),
                 TextWidth::new_for_testing(1)
             ),
             (
                 SyntaxKind::Trivia,
                 None,
-                TextOffset::default().add_width(TextWidth::new_for_testing(7)),
+                TextWidth::new_for_testing(7).as_offset(),
                 TextWidth::new_for_testing(0)
             )
         ]

crates/cairo-lang-syntax/src/node/mod.rs

@@ -49,7 +49,7 @@ impl SyntaxNode {
     pub fn new_root(db: &dyn SyntaxGroup, file_id: FileId, green: GreenId) -> Self {
         let inner = SyntaxNodeInner {
             green,
-            offset: TextOffset::default(),
+            offset: TextOffset::START,
             parent: None,
             stable_ptr: SyntaxStablePtr::Root(file_id, green).intern(db),
         };
@@ -272,11 +272,10 @@ impl SyntaxNode {
         let orig_span = self.span(db);
         assert!(orig_span.contains(span));
         let full_text = self.get_text(db);
-        let zero_offset = TextOffset::default();
 
         let span_in_span = TextSpan {
-            start: zero_offset.add_width(span.start - orig_span.start),
-            end: zero_offset.add_width(span.end - orig_span.start),
+            start: (span.start - orig_span.start).as_offset(),
+            end: (span.end - orig_span.start).as_offset(),
         };
         span_in_span.take(&full_text).to_string()
     }