1 //===--- TextDiagnostic.h - Text Diagnostic Pretty-Printing -----*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This is a utility class that provides support for textual pretty-printing of
11 // diagnostics. It is used to implement the different code paths which require
12 // such functionality in a consistent way.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #ifndef LLVM_CLANG_FRONTEND_TEXTDIAGNOSTIC_H
17 #define LLVM_CLANG_FRONTEND_TEXTDIAGNOSTIC_H
18 
19 #include "clang/Frontend/DiagnosticRenderer.h"
20 
21 namespace clang {
22 
23 /// \brief Class to encapsulate the logic for formatting and printing a textual
24 /// diagnostic message.
25 ///
26 /// This class provides an interface for building and emitting a textual
27 /// diagnostic, including all of the macro backtraces, caret diagnostics, FixIt
28 /// Hints, and code snippets. In the presence of macros this involves
29 /// a recursive process, synthesizing notes for each macro expansion.
30 ///
31 /// The purpose of this class is to isolate the implementation of printing
32 /// beautiful text diagnostics from any particular interfaces. The Clang
33 /// DiagnosticClient is implemented through this class as is diagnostic
34 /// printing coming out of libclang.
35 class TextDiagnostic : public DiagnosticRenderer {
36   raw_ostream &OS;
37 
38 public:
39   TextDiagnostic(raw_ostream &OS,
40                  const LangOptions &LangOpts,
41                  DiagnosticOptions *DiagOpts);
42 
43   ~TextDiagnostic() override;
44 
45   /// \brief Print the diagonstic level to a raw_ostream.
46   ///
47   /// This is a static helper that handles colorizing the level and formatting
48   /// it into an arbitrary output stream. This is used internally by the
49   /// TextDiagnostic emission code, but it can also be used directly by
50   /// consumers that don't have a source manager or other state that the full
51   /// TextDiagnostic logic requires.
52   static void printDiagnosticLevel(raw_ostream &OS,
53                                    DiagnosticsEngine::Level Level,
54                                    bool ShowColors,
55                                    bool CLFallbackMode = false);
56 
57   /// \brief Pretty-print a diagnostic message to a raw_ostream.
58   ///
59   /// This is a static helper to handle the line wrapping, colorizing, and
60   /// rendering of a diagnostic message to a particular ostream. It is
61   /// publicly visible so that clients which do not have sufficient state to
62   /// build a complete TextDiagnostic object can still get consistent
63   /// formatting of their diagnostic messages.
64   ///
65   /// \param OS Where the message is printed
66   /// \param IsSupplemental true if this is a continuation note diagnostic
67   /// \param Message The text actually printed
68   /// \param CurrentColumn The starting column of the first line, accounting
69   ///                      for any prefix.
70   /// \param Columns The number of columns to use in line-wrapping, 0 disables
71   ///                all line-wrapping.
72   /// \param ShowColors Enable colorizing of the message.
73   static void printDiagnosticMessage(raw_ostream &OS, bool IsSupplemental,
74                                      StringRef Message, unsigned CurrentColumn,
75                                      unsigned Columns, bool ShowColors);
76 
77 protected:
78   void emitDiagnosticMessage(SourceLocation Loc,PresumedLoc PLoc,
79                              DiagnosticsEngine::Level Level,
80                              StringRef Message,
81                              ArrayRef<CharSourceRange> Ranges,
82                              const SourceManager *SM,
83                              DiagOrStoredDiag D) override;
84 
85   void emitDiagnosticLoc(SourceLocation Loc, PresumedLoc PLoc,
86                          DiagnosticsEngine::Level Level,
87                          ArrayRef<CharSourceRange> Ranges,
88                          const SourceManager &SM) override;
89 
emitCodeContext(SourceLocation Loc,DiagnosticsEngine::Level Level,SmallVectorImpl<CharSourceRange> & Ranges,ArrayRef<FixItHint> Hints,const SourceManager & SM)90   void emitCodeContext(SourceLocation Loc,
91                        DiagnosticsEngine::Level Level,
92                        SmallVectorImpl<CharSourceRange>& Ranges,
93                        ArrayRef<FixItHint> Hints,
94                        const SourceManager &SM) override {
95     emitSnippetAndCaret(Loc, Level, Ranges, Hints, SM);
96   }
97 
98   void emitIncludeLocation(SourceLocation Loc, PresumedLoc PLoc,
99                            const SourceManager &SM) override;
100 
101   void emitImportLocation(SourceLocation Loc, PresumedLoc PLoc,
102                           StringRef ModuleName,
103                           const SourceManager &SM) override;
104 
105   void emitBuildingModuleLocation(SourceLocation Loc, PresumedLoc PLoc,
106                                   StringRef ModuleName,
107                                   const SourceManager &SM) override;
108 
109 private:
110   void emitSnippetAndCaret(SourceLocation Loc, DiagnosticsEngine::Level Level,
111                            SmallVectorImpl<CharSourceRange>& Ranges,
112                            ArrayRef<FixItHint> Hints,
113                            const SourceManager &SM);
114 
115   void emitSnippet(StringRef SourceLine);
116 
117   void emitParseableFixits(ArrayRef<FixItHint> Hints, const SourceManager &SM);
118 };
119 
120 } // end namespace clang
121 
122 #endif
123