1 //===--- Config.h - User configuration of clangd behavior --------*- C++-*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // Various clangd features have configurable behaviour (or can be disabled).
10 // This file defines "resolved" configuration seen by features within clangd.
11 // For example, settings may vary per-file, the resolved Config only contains
12 // settings that apply to the current file.
13 //
14 // This is distinct from how the config is specified by the user (Fragment)
15 // interpreted (CompiledFragment), and combined (Provider).
16 // ConfigFragment.h describes the steps to add a new configuration option.
17 //
18 // Because this structure is shared throughout clangd, it's a potential source
19 // of layering problems. Config should be expressed in terms of simple
20 // vocabulary types where possible.
21 //
22 //===----------------------------------------------------------------------===//
23 
24 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_CONFIG_H
25 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_CONFIG_H
26 
27 #include "support/Context.h"
28 #include "llvm/ADT/FunctionExtras.h"
29 #include "llvm/ADT/Optional.h"
30 #include "llvm/ADT/StringMap.h"
31 #include "llvm/ADT/StringSet.h"
32 #include <functional>
33 #include <string>
34 #include <vector>
35 
36 namespace clang {
37 namespace clangd {
38 
39 /// Settings that express user/project preferences and control clangd behavior.
40 ///
41 /// Generally, features should consume Config::current() and the caller is
42 /// responsible for setting it appropriately. In practice these callers are
43 /// ClangdServer, TUScheduler, and BackgroundQueue.
44 struct Config {
45   /// Returns the Config of the current Context, or an empty configuration.
46   static const Config &current();
47   /// Context key which can be used to set the current Config.
48   static clangd::Key<Config> Key;
49 
50   Config() = default;
51   Config(const Config &) = delete;
52   Config &operator=(const Config &) = delete;
53   Config(Config &&) = default;
54   Config &operator=(Config &&) = default;
55 
56   struct CDBSearchSpec {
57     enum { Ancestors, FixedDir, NoCDBSearch } Policy = Ancestors;
58     // Absolute, native slashes, no trailing slash.
59     llvm::Optional<std::string> FixedCDBPath;
60   };
61 
62   /// Controls how the compile command for the current file is determined.
63   struct {
64     /// Edits to apply to the compile command, in sequence.
65     std::vector<llvm::unique_function<void(std::vector<std::string> &) const>>
66         Edits;
67     /// Where to search for compilation databases for this file's flags.
68     CDBSearchSpec CDBSearch = {CDBSearchSpec::Ancestors, llvm::None};
69   } CompileFlags;
70 
71   enum class BackgroundPolicy { Build, Skip };
72   /// Describes an external index configuration.
73   struct ExternalIndexSpec {
74     enum { None, File, Server } Kind = None;
75     /// This is one of:
76     /// - Address of a clangd-index-server, in the form of "ip:port".
77     /// - Absolute path to an index produced by clangd-indexer.
78     std::string Location;
79     /// Absolute path to source root this index is associated with, uses
80     /// forward-slashes.
81     std::string MountPoint;
82   };
83   /// Controls index behavior.
84   struct {
85     /// Whether this TU should be background-indexed.
86     BackgroundPolicy Background = BackgroundPolicy::Build;
87     ExternalIndexSpec External;
88     bool StandardLibrary = false;
89   } Index;
90 
91   enum UnusedIncludesPolicy { Strict, None };
92   /// Controls warnings and errors when parsing code.
93   struct {
94     bool SuppressAll = false;
95     llvm::StringSet<> Suppress;
96 
97     /// Configures what clang-tidy checks to run and options to use with them.
98     struct {
99       // A comma-seperated list of globs specify which clang-tidy checks to run.
100       std::string Checks;
101       llvm::StringMap<std::string> CheckOptions;
102     } ClangTidy;
103 
104     UnusedIncludesPolicy UnusedIncludes = None;
105 
106     /// IncludeCleaner will not diagnose usages of these headers matched by
107     /// these regexes.
108     struct {
109       std::vector<std::function<bool(llvm::StringRef)>> IgnoreHeader;
110     } Includes;
111   } Diagnostics;
112 
113   /// Style of the codebase.
114   struct {
115     // Namespaces that should always be fully qualified, meaning no "using"
116     // declarations, always spell out the whole name (with or without leading
117     // ::). All nested namespaces are affected as well.
118     std::vector<std::string> FullyQualifiedNamespaces;
119   } Style;
120 
121   /// Configures code completion feature.
122   struct {
123     /// Whether code completion includes results that are not visible in current
124     /// scopes.
125     bool AllScopes = true;
126   } Completion;
127 
128   /// Configures hover feature.
129   struct {
130     /// Whether hover show a.k.a type.
131     bool ShowAKA = true;
132   } Hover;
133 
134   struct {
135     /// If false, inlay hints are completely disabled.
136     bool Enabled = true;
137 
138     // Whether specific categories of hints are enabled.
139     bool Parameters = true;
140     bool DeducedTypes = true;
141     bool Designators = true;
142   } InlayHints;
143 };
144 
145 } // namespace clangd
146 } // namespace clang
147 
148 namespace llvm {
149 template <> struct DenseMapInfo<clang::clangd::Config::ExternalIndexSpec> {
150   using ExternalIndexSpec = clang::clangd::Config::ExternalIndexSpec;
151   static inline ExternalIndexSpec getEmptyKey() {
152     return {ExternalIndexSpec::File, "", ""};
153   }
154   static inline ExternalIndexSpec getTombstoneKey() {
155     return {ExternalIndexSpec::File, "TOMB", "STONE"};
156   }
157   static unsigned getHashValue(const ExternalIndexSpec &Val) {
158     return llvm::hash_combine(Val.Kind, Val.Location, Val.MountPoint);
159   }
160   static bool isEqual(const ExternalIndexSpec &LHS,
161                       const ExternalIndexSpec &RHS) {
162     return std::tie(LHS.Kind, LHS.Location, LHS.MountPoint) ==
163            std::tie(RHS.Kind, RHS.Location, RHS.MountPoint);
164   }
165 };
166 } // namespace llvm
167 
168 #endif
169