1 files changed, 94 insertions, 0 deletions
diff --git a/compiler/rustc_ast_pretty/src/pp/convenience.rs b/compiler/rustc_ast_pretty/src/pp/convenience.rs
new file mode 100644
index 000000000..93310dd45
--- /dev/null
+++ b/compiler/rustc_ast_pretty/src/pp/convenience.rs
@@ -0,0 +1,94 @@
+use crate::pp::{BeginToken, BreakToken, Breaks, IndentStyle, Printer, Token, SIZE_INFINITY};
+use std::borrow::Cow;
+
+impl Printer {
+    /// "raw box"
+    pub fn rbox(&mut self, indent: isize, breaks: Breaks) {
+        self.scan_begin(BeginToken { indent: IndentStyle::Block { offset: indent }, breaks })
+    }
+
+    /// Inconsistent breaking box
+    pub fn ibox(&mut self, indent: isize) {
+        self.rbox(indent, Breaks::Inconsistent)
+    }
+
+    /// Consistent breaking box
+    pub fn cbox(&mut self, indent: isize) {
+        self.rbox(indent, Breaks::Consistent)
+    }
+
+    pub fn visual_align(&mut self) {
+        self.scan_begin(BeginToken { indent: IndentStyle::Visual, breaks: Breaks::Consistent });
+    }
+
+    pub fn break_offset(&mut self, n: usize, off: isize) {
+        self.scan_break(BreakToken {
+            offset: off,
+            blank_space: n as isize,
+            ..BreakToken::default()
+        });
+    }
+
+    pub fn end(&mut self) {
+        self.scan_end()
+    }
+
+    pub fn eof(mut self) -> String {
+        self.scan_eof();
+        self.out
+    }
+
+    pub fn word<S: Into<Cow<'static, str>>>(&mut self, wrd: S) {
+        let string = wrd.into();
+        self.scan_string(string)
+    }
+
+    fn spaces(&mut self, n: usize) {
+        self.break_offset(n, 0)
+    }
+
+    pub fn zerobreak(&mut self) {
+        self.spaces(0)
+    }
+
+    pub fn space(&mut self) {
+        self.spaces(1)
+    }
+
+    pub fn hardbreak(&mut self) {
+        self.spaces(SIZE_INFINITY as usize)
+    }
+
+    pub fn is_beginning_of_line(&self) -> bool {
+        match self.last_token() {
+            Some(last_token) => last_token.is_hardbreak_tok(),
+            None => true,
+        }
+    }
+
+    pub fn hardbreak_tok_offset(off: isize) -> Token {
+        Token::Break(BreakToken {
+            offset: off,
+            blank_space: SIZE_INFINITY,
+            ..BreakToken::default()
+        })
+    }
+
+    pub fn trailing_comma(&mut self) {
+        self.scan_break(BreakToken { pre_break: Some(','), ..BreakToken::default() });
+    }
+
+    pub fn trailing_comma_or_space(&mut self) {
+        self.scan_break(BreakToken {
+            blank_space: 1,
+            pre_break: Some(','),
+            ..BreakToken::default()
+        });
+    }
+}
+
+impl Token {
+    pub fn is_hardbreak_tok(&self) -> bool {
+        *self == Printer::hardbreak_tok_offset(0)
+    }
+}