//===- VerifyDiagnosticConsumer.h - Verifying Diagnostic Client -*- C++ -*-===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_FRONTEND_VERIFYDIAGNOSTICCONSUMER_H

#define LLVM_CLANG_FRONTEND_VERIFYDIAGNOSTICCONSUMER_H

#include "clang/Basic/Diagnostic.h"

#include "clang/Basic/LLVM.h"

#include "clang/Basic/SourceLocation.h"

#include "clang/Lex/Preprocessor.h"

#include "llvm/ADT/DenseMap.h"

#include "llvm/ADT/PointerIntPair.h"

#include "llvm/ADT/StringRef.h"

#include <cassert>

#include <limits>

#include <memory>

#include <string>

#include <vector>

namespace clang {

class FileEntry;

class LangOptions;

class SourceManager;

class TextDiagnosticBuffer;

/// VerifyDiagnosticConsumer - Create a diagnostic client which will use

/// markers in the input source to check that all the emitted diagnostics match

/// those expected.

///

/// INVOKING THE DIAGNOSTIC CHECKER:

///

/// VerifyDiagnosticConsumer is typically invoked via the "-verify" option to

/// "clang -cc1".  "-verify" is equivalent to "-verify=expected", so all

/// diagnostics are typically specified with the prefix "expected".  For

/// example:

///

/// \code

///   int A = B; // expected-error {{use of undeclared identifier 'B'}}

/// \endcode

///

/// Custom prefixes can be specified as a comma-separated sequence.  Each

/// prefix must start with a letter and contain only alphanumeric characters,

/// hyphens, and underscores.  For example, given just "-verify=foo,bar",

/// the above diagnostic would be ignored, but the following diagnostics would

/// be recognized:

///

/// \code

///   int A = B; // foo-error {{use of undeclared identifier 'B'}}

///   int C = D; // bar-error {{use of undeclared identifier 'D'}}

/// \endcode

///

/// Multiple occurrences accumulate prefixes.  For example,

/// "-verify -verify=foo,bar -verify=baz" is equivalent to

/// "-verify=expected,foo,bar,baz".

///

/// SPECIFYING DIAGNOSTICS:

///

/// Indicating that a line expects an error or a warning is simple. Put a

/// comment on the line that has the diagnostic, use:

///

/// \code

///   expected-{error,warning,remark,note}

/// \endcode

///

/// to tag if it's an expected error, remark or warning, and place the expected

/// text between {{ and }} markers. The full text doesn't have to be included,

/// only enough to ensure that the correct diagnostic was emitted.

///

/// Here's an example:

///

/// \code

///   int A = B; // expected-error {{use of undeclared identifier 'B'}}

/// \endcode

///

/// You can place as many diagnostics on one line as you wish. To make the code

/// more readable, you can use slash-newline to separate out the diagnostics.

///

/// Alternatively, it is possible to specify the line on which the diagnostic

/// should appear by appending "@<line>" to "expected-<type>", for example:

///

/// \code

///   #warning some text

///   // expected-warning@10 {{some text}}

/// \endcode

///

/// The line number may be absolute (as above), or relative to the current

/// line by prefixing the number with either '+' or '-'.

///

/// If the diagnostic is generated in a separate file, for example in a shared

/// header file, it may be beneficial to be able to declare the file in which

/// the diagnostic will appear, rather than placing the expected-* directive in

/// the actual file itself.  This can be done using the following syntax:

///

/// \code

///   // expected-error@path/include.h:15 {{error message}}

/// \endcode

///

/// The path can be absolute or relative and the same search paths will be used

/// as for #include directives.  The line number in an external file may be

/// substituted with '*' meaning that any line number will match (useful where

/// the included file is, for example, a system header where the actual line

/// number may change and is not critical).

///

/// As an alternative to specifying a fixed line number, the location of a

/// diagnostic can instead be indicated by a marker of the form "#<marker>".

/// Markers are specified by including them in a comment, and then referenced

/// by appending the marker to the diagnostic with "@#<marker>":

///

/// \code

///   #warning some text  // #1

///   // expected-warning@#1 {{some text}}

/// \endcode

///

/// The name of a marker used in a directive must be unique within the

/// compilation.

///

/// The simple syntax above allows each specification to match exactly one

/// error.  You can use the extended syntax to customize this. The extended

/// syntax is "expected-<type> <n> {{diag text}}", where \<type> is one of

/// "error", "warning" or "note", and \<n> is a positive integer. This allows

/// the diagnostic to appear as many times as specified. Example:

///

/// \code

///   void f(); // expected-note 2 {{previous declaration is here}}

/// \endcode

///

/// Where the diagnostic is expected to occur a minimum number of times, this

/// can be specified by appending a '+' to the number. Example:

///

/// \code

///   void f(); // expected-note 0+ {{previous declaration is here}}

///   void g(); // expected-note 1+ {{previous declaration is here}}

/// \endcode

///

/// In the first example, the diagnostic becomes optional, i.e. it will be

/// swallowed if it occurs, but will not generate an error if it does not

/// occur.  In the second example, the diagnostic must occur at least once.

/// As a short-hand, "one or more" can be specified simply by '+'. Example:

///

/// \code

///   void g(); // expected-note + {{previous declaration is here}}

/// \endcode

///

/// A range can also be specified by "<n>-<m>".  Example:

///

/// \code

///   void f(); // expected-note 0-1 {{previous declaration is here}}

/// \endcode

///

/// In this example, the diagnostic may appear only once, if at all.

///

/// Regex matching mode may be selected by appending '-re' to type and

/// including regexes wrapped in double curly braces in the directive, such as:

///

/// \code

///   expected-error-re {{format specifies type 'wchar_t **' (aka '{{.+}}')}}

/// \endcode

///

/// Examples matching error: "variable has incomplete type 'struct s'"

///

/// \code

///   // expected-error {{variable has incomplete type 'struct s'}}

///   // expected-error {{variable has incomplete type}}

///

///   // expected-error-re {{variable has type 'struct {{.}}'}}

///   // expected-error-re {{variable has type 'struct {{.*}}'}}

///   // expected-error-re {{variable has type 'struct {{(.*)}}'}}

///   // expected-error-re {{variable has type 'struct{{[[:space:]](.*)}}'}}

/// \endcode

///

/// VerifyDiagnosticConsumer expects at least one expected-* directive to

/// be found inside the source code.  If no diagnostics are expected the

/// following directive can be used to indicate this:

///

/// \code

///   // expected-no-diagnostics

/// \endcode

///

class VerifyDiagnosticConsumer: public DiagnosticConsumer,

                                public CommentHandler {

public:

  /// Directive - Abstract class representing a parsed verify directive.

  ///

  class Directive {

  public:

    static std::unique_ptr<Directive> create(bool RegexKind,

                                             SourceLocation DirectiveLoc,

                                             SourceLocation DiagnosticLoc,

                                             bool MatchAnyLine, StringRef Text,

                                             unsigned Min, unsigned Max);

  public:

    /// Constant representing n or more matches.

    static const unsigned MaxCount = std::numeric_limits<unsigned>::max();

    SourceLocation DirectiveLoc;

    SourceLocation DiagnosticLoc;

    const std::string Text;

    unsigned Min, Max;

    bool MatchAnyLine;

    Directive(const Directive &) = delete;

    Directive &operator=(const Directive &) = delete;

    virtual ~Directive() = default;

    // Returns true if directive text is valid.

    // Otherwise returns false and populates E.

    virtual bool isValid(std::string &Error) = 0;

    // Returns true on match.

    virtual bool match(StringRef S) = 0;

  protected:

    Directive(SourceLocation DirectiveLoc, SourceLocation DiagnosticLoc,

              bool MatchAnyLine, StringRef Text, unsigned Min, unsigned Max)

        : DirectiveLoc(DirectiveLoc), DiagnosticLoc(DiagnosticLoc),

          Text(Text), Min(Min), Max(Max), MatchAnyLine(MatchAnyLine) {

      assert(!DirectiveLoc.isInvalid() && "DirectiveLoc is invalid!");

      assert((!DiagnosticLoc.isInvalid() || MatchAnyLine) &&

             "DiagnosticLoc is invalid!");

    }

  };

  using DirectiveList = std::vector<std::unique_ptr<Directive>>;

  /// ExpectedData - owns directive objects and deletes on destructor.

  struct ExpectedData {

    DirectiveList Errors;

    DirectiveList Warnings;

    DirectiveList Remarks;

    DirectiveList Notes;

    void Reset() {

      Errors.clear();

      Warnings.clear();

      Remarks.clear();

      Notes.clear();

    }

  };

  enum DirectiveStatus {

    HasNoDirectives,

    HasNoDirectivesReported,

    HasExpectedNoDiagnostics,

    HasOtherExpectedDirectives

  };

  class MarkerTracker;

private:

  DiagnosticsEngine &Diags;

  DiagnosticConsumer *PrimaryClient;

  std::unique_ptr<DiagnosticConsumer> PrimaryClientOwner;

  std::unique_ptr<TextDiagnosticBuffer> Buffer;

  std::unique_ptr<MarkerTracker> Markers;

  const Preprocessor *CurrentPreprocessor = nullptr;

  const LangOptions *LangOpts = nullptr;

  SourceManager *SrcManager = nullptr;

  unsigned ActiveSourceFiles = 0;

  DirectiveStatus Status;

  ExpectedData ED;

  void CheckDiagnostics();

  void setSourceManager(SourceManager &SM) {

    assert((!SrcManager || SrcManager == &SM) && "SourceManager changed!");

    SrcManager = &SM;

  }

  // These facilities are used for validation in debug builds.

  class UnparsedFileStatus {

    llvm::PointerIntPair<const FileEntry *, 1, bool> Data;

  public:

    UnparsedFileStatus(const FileEntry *File, bool FoundDirectives)

        : Data(File, FoundDirectives) {}

    const FileEntry *getFile() const { return Data.getPointer(); }

    bool foundDirectives() const { return Data.getInt(); }

  };

  using ParsedFilesMap = llvm::DenseMap<FileID, const FileEntry *>;

  using UnparsedFilesMap = llvm::DenseMap<FileID, UnparsedFileStatus>;

  ParsedFilesMap ParsedFiles;

  UnparsedFilesMap UnparsedFiles;

public:

  /// Create a new verifying diagnostic client, which will issue errors to

  /// the currently-attached diagnostic client when a diagnostic does not match

  /// what is expected (as indicated in the source file).

  VerifyDiagnosticConsumer(DiagnosticsEngine &Diags);

  ~VerifyDiagnosticConsumer() override;

  void BeginSourceFile(const LangOptions &LangOpts,

                       const Preprocessor *PP) override;

  void EndSourceFile() override;

  enum ParsedStatus {

    /// File has been processed via HandleComment.

    IsParsed,

    /// File has diagnostics and may have directives.

    IsUnparsed,

    /// File has diagnostics but guaranteed no directives.

    IsUnparsedNoDirectives

  };

  /// Update lists of parsed and unparsed files.

  void UpdateParsedFileStatus(SourceManager &SM, FileID FID, ParsedStatus PS);

  bool HandleComment(Preprocessor &PP, SourceRange Comment) override;

  void HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,

                        const Diagnostic &Info) override;

};

} // namespace clang

#endif // LLVM_CLANG_FRONTEND_VERIFYDIAGNOSTICCONSUMER_H