| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `crates/rust-analyzer/src/discover.rs`."><title>discover.rs - source</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-6b053e98.ttf.woff2,FiraSans-Italic-81dc35de.woff2,FiraSans-Regular-0fe48ade.woff2,FiraSans-MediumItalic-ccf7e434.woff2,FiraSans-Medium-e1aa3f0a.woff2,SourceCodePro-Regular-8badfe75.ttf.woff2,SourceCodePro-Semibold-aa29a496.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2"href="../../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../../static.files/normalize-9960930a.css"><link rel="stylesheet" href="../../static.files/rustdoc-77263533.css"><meta name="rustdoc-vars" data-root-path="../../" data-static-root-path="../../static.files/" data-current-crate="rust_analyzer" data-themes="" data-resource-suffix="" data-rustdoc-version="1.94.0 (4a4ef493e 2026-03-02)" data-channel="1.94.0" data-search-js="search-9e2438ea.js" data-stringdex-js="stringdex-b897f86f.js" data-settings-js="settings-c38705f0.js" ><script src="../../static.files/storage-e2aeef58.js"></script><script defer src="../../static.files/src-script-813739b1.js"></script><script defer src="../../src-files.js"></script><script defer src="../../static.files/main-7bab91a1.js"></script><noscript><link rel="stylesheet" href="../../static.files/noscript-ffcac47a.css"></noscript><link rel="alternate icon" type="image/png" href="../../static.files/favicon-32x32-eab170b8.png"><link rel="icon" type="image/svg+xml" href="../../static.files/favicon-044be391.svg"></head><body class="rustdoc src"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><div class="src-sidebar-title"><h2>Files</h2></div></nav><div class="sidebar-resizer" title="Drag to resize sidebar"></div><main><section id="main-content" class="content"><div class="main-heading"><h1><div class="sub-heading">rust_analyzer/</div>discover.rs</h1><rustdoc-toolbar></rustdoc-toolbar></div><div class="example-wrap digits-3"><pre class="rust"><code><a href=#1 id=1 data-nosnippet>1</a><span class="doccomment">//! Infrastructure for lazy project discovery. Currently only support rust-project.json discovery |
| <a href=#2 id=2 data-nosnippet>2</a>//! via a custom discover command. |
| <a href=#3 id=3 data-nosnippet>3</a></span><span class="kw">use </span>std::path::Path; |
| <a href=#4 id=4 data-nosnippet>4</a> |
| <a href=#5 id=5 data-nosnippet>5</a><span class="kw">use </span>crossbeam_channel::Sender; |
| <a href=#6 id=6 data-nosnippet>6</a><span class="kw">use </span>ide_db::FxHashMap; |
| <a href=#7 id=7 data-nosnippet>7</a><span class="kw">use </span>paths::{AbsPathBuf, Utf8Path, Utf8PathBuf}; |
| <a href=#8 id=8 data-nosnippet>8</a><span class="kw">use </span>project_model::ProjectJsonData; |
| <a href=#9 id=9 data-nosnippet>9</a><span class="kw">use </span>serde::{Deserialize, Serialize}; |
| <a href=#10 id=10 data-nosnippet>10</a><span class="kw">use </span>tracing::{info_span, span::EnteredSpan}; |
| <a href=#11 id=11 data-nosnippet>11</a> |
| <a href=#12 id=12 data-nosnippet>12</a><span class="kw">use </span><span class="kw">crate</span>::command::{CommandHandle, JsonLinesParser}; |
| <a href=#13 id=13 data-nosnippet>13</a> |
| <a href=#14 id=14 data-nosnippet>14</a><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">const </span>ARG_PLACEHOLDER: <span class="kw-2">&</span>str = <span class="string">"{arg}"</span>; |
| <a href=#15 id=15 data-nosnippet>15</a> |
| <a href=#16 id=16 data-nosnippet>16</a><span class="doccomment">/// A command wrapper for getting a `rust-project.json`. |
| <a href=#17 id=17 data-nosnippet>17</a>/// |
| <a href=#18 id=18 data-nosnippet>18</a>/// This is analogous to discovering a cargo project + running `cargo-metadata` on it, but for non-Cargo build systems. |
| <a href=#19 id=19 data-nosnippet>19</a></span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>DiscoverCommand { |
| <a href=#20 id=20 data-nosnippet>20</a> command: Vec<String>, |
| <a href=#21 id=21 data-nosnippet>21</a> sender: Sender<DiscoverProjectMessage>, |
| <a href=#22 id=22 data-nosnippet>22</a>} |
| <a href=#23 id=23 data-nosnippet>23</a> |
| <a href=#24 id=24 data-nosnippet>24</a><span class="attr">#[derive(PartialEq, Clone, Debug, Serialize)] |
| <a href=#25 id=25 data-nosnippet>25</a>#[serde(rename_all = <span class="string">"camelCase"</span>)] |
| <a href=#26 id=26 data-nosnippet>26</a></span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">enum </span>DiscoverArgument { |
| <a href=#27 id=27 data-nosnippet>27</a> Path(<span class="attr">#[serde(serialize_with = <span class="string">"serialize_abs_pathbuf"</span>)] </span>AbsPathBuf), |
| <a href=#28 id=28 data-nosnippet>28</a> Buildfile(<span class="attr">#[serde(serialize_with = <span class="string">"serialize_abs_pathbuf"</span>)] </span>AbsPathBuf), |
| <a href=#29 id=29 data-nosnippet>29</a>} |
| <a href=#30 id=30 data-nosnippet>30</a> |
| <a href=#31 id=31 data-nosnippet>31</a><span class="kw">fn </span>serialize_abs_pathbuf<S>(path: <span class="kw-2">&</span>AbsPathBuf, se: S) -> <span class="prelude-ty">Result</span><S::Ok, S::Error> |
| <a href=#32 id=32 data-nosnippet>32</a><span class="kw">where |
| <a href=#33 id=33 data-nosnippet>33</a> </span>S: serde::Serializer, |
| <a href=#34 id=34 data-nosnippet>34</a>{ |
| <a href=#35 id=35 data-nosnippet>35</a> <span class="kw">let </span>path: <span class="kw-2">&</span>Utf8Path = path.as_ref(); |
| <a href=#36 id=36 data-nosnippet>36</a> se.serialize_str(path.as_str()) |
| <a href=#37 id=37 data-nosnippet>37</a>} |
| <a href=#38 id=38 data-nosnippet>38</a> |
| <a href=#39 id=39 data-nosnippet>39</a><span class="kw">impl </span>DiscoverCommand { |
| <a href=#40 id=40 data-nosnippet>40</a> <span class="doccomment">/// Create a new [DiscoverCommand]. |
| <a href=#41 id=41 data-nosnippet>41</a> </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>new(sender: Sender<DiscoverProjectMessage>, command: Vec<String>) -> <span class="self">Self </span>{ |
| <a href=#42 id=42 data-nosnippet>42</a> <span class="self">Self </span>{ sender, command } |
| <a href=#43 id=43 data-nosnippet>43</a> } |
| <a href=#44 id=44 data-nosnippet>44</a> |
| <a href=#45 id=45 data-nosnippet>45</a> <span class="doccomment">/// Spawn the command inside `DiscoverCommand` and report progress, if any. |
| <a href=#46 id=46 data-nosnippet>46</a> </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>spawn( |
| <a href=#47 id=47 data-nosnippet>47</a> <span class="kw-2">&</span><span class="self">self</span>, |
| <a href=#48 id=48 data-nosnippet>48</a> discover_arg: DiscoverArgument, |
| <a href=#49 id=49 data-nosnippet>49</a> current_dir: <span class="kw-2">&</span>Path, |
| <a href=#50 id=50 data-nosnippet>50</a> ) -> anyhow::Result<DiscoverHandle> { |
| <a href=#51 id=51 data-nosnippet>51</a> <span class="kw">let </span>command = <span class="kw-2">&</span><span class="self">self</span>.command[<span class="number">0</span>]; |
| <a href=#52 id=52 data-nosnippet>52</a> <span class="kw">let </span>args = <span class="kw-2">&</span><span class="self">self</span>.command[<span class="number">1</span>..]; |
| <a href=#53 id=53 data-nosnippet>53</a> |
| <a href=#54 id=54 data-nosnippet>54</a> <span class="kw">let </span>args: Vec<String> = args |
| <a href=#55 id=55 data-nosnippet>55</a> .iter() |
| <a href=#56 id=56 data-nosnippet>56</a> .map(|arg| { |
| <a href=#57 id=57 data-nosnippet>57</a> <span class="kw">if </span>arg == ARG_PLACEHOLDER { |
| <a href=#58 id=58 data-nosnippet>58</a> serde_json::to_string(<span class="kw-2">&</span>discover_arg).expect(<span class="string">"Unable to serialize args"</span>) |
| <a href=#59 id=59 data-nosnippet>59</a> } <span class="kw">else </span>{ |
| <a href=#60 id=60 data-nosnippet>60</a> arg.to_owned() |
| <a href=#61 id=61 data-nosnippet>61</a> } |
| <a href=#62 id=62 data-nosnippet>62</a> }) |
| <a href=#63 id=63 data-nosnippet>63</a> .collect(); |
| <a href=#64 id=64 data-nosnippet>64</a> |
| <a href=#65 id=65 data-nosnippet>65</a> <span class="comment">// TODO: are we sure the extra env should be empty? |
| <a href=#66 id=66 data-nosnippet>66</a> </span><span class="kw">let </span><span class="kw-2">mut </span>cmd = toolchain::command(command, current_dir, <span class="kw-2">&</span>FxHashMap::default()); |
| <a href=#67 id=67 data-nosnippet>67</a> cmd.args(args); |
| <a href=#68 id=68 data-nosnippet>68</a> |
| <a href=#69 id=69 data-nosnippet>69</a> <span class="prelude-val">Ok</span>(DiscoverHandle { |
| <a href=#70 id=70 data-nosnippet>70</a> handle: CommandHandle::spawn(cmd, DiscoverProjectParser, <span class="self">self</span>.sender.clone(), <span class="prelude-val">None</span>)<span class="question-mark">?</span>, |
| <a href=#71 id=71 data-nosnippet>71</a> span: <span class="macro">info_span!</span>(<span class="string">"discover_command"</span>).entered(), |
| <a href=#72 id=72 data-nosnippet>72</a> }) |
| <a href=#73 id=73 data-nosnippet>73</a> } |
| <a href=#74 id=74 data-nosnippet>74</a>} |
| <a href=#75 id=75 data-nosnippet>75</a> |
| <a href=#76 id=76 data-nosnippet>76</a><span class="doccomment">/// A handle to a spawned `DiscoverCommand`. |
| <a href=#77 id=77 data-nosnippet>77</a></span><span class="attr">#[derive(Debug)] |
| <a href=#78 id=78 data-nosnippet>78</a></span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>DiscoverHandle { |
| <a href=#79 id=79 data-nosnippet>79</a> <span class="kw">pub</span>(<span class="kw">crate</span>) handle: CommandHandle<DiscoverProjectMessage>, |
| <a href=#80 id=80 data-nosnippet>80</a> <span class="attr">#[allow(dead_code)] </span><span class="comment">// not accessed, but used to log on drop. |
| <a href=#81 id=81 data-nosnippet>81</a> </span>span: EnteredSpan, |
| <a href=#82 id=82 data-nosnippet>82</a>} |
| <a href=#83 id=83 data-nosnippet>83</a> |
| <a href=#84 id=84 data-nosnippet>84</a><span class="doccomment">/// An enum containing either progress messages, an error, |
| <a href=#85 id=85 data-nosnippet>85</a>/// or the materialized `rust-project`. |
| <a href=#86 id=86 data-nosnippet>86</a></span><span class="attr">#[derive(Debug, Clone, Deserialize, Serialize)] |
| <a href=#87 id=87 data-nosnippet>87</a>#[serde(tag = <span class="string">"kind"</span>)] |
| <a href=#88 id=88 data-nosnippet>88</a>#[serde(rename_all = <span class="string">"snake_case"</span>)] |
| <a href=#89 id=89 data-nosnippet>89</a></span><span class="kw">enum </span>DiscoverProjectData { |
| <a href=#90 id=90 data-nosnippet>90</a> Finished { buildfile: Utf8PathBuf, project: ProjectJsonData }, |
| <a href=#91 id=91 data-nosnippet>91</a> Error { error: String, source: <span class="prelude-ty">Option</span><String> }, |
| <a href=#92 id=92 data-nosnippet>92</a> Progress { message: String }, |
| <a href=#93 id=93 data-nosnippet>93</a>} |
| <a href=#94 id=94 data-nosnippet>94</a> |
| <a href=#95 id=95 data-nosnippet>95</a><span class="attr">#[derive(Debug, PartialEq, Clone)] |
| <a href=#96 id=96 data-nosnippet>96</a></span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">enum </span>DiscoverProjectMessage { |
| <a href=#97 id=97 data-nosnippet>97</a> Finished { project: ProjectJsonData, buildfile: AbsPathBuf }, |
| <a href=#98 id=98 data-nosnippet>98</a> Error { error: String, source: <span class="prelude-ty">Option</span><String> }, |
| <a href=#99 id=99 data-nosnippet>99</a> Progress { message: String }, |
| <a href=#100 id=100 data-nosnippet>100</a>} |
| <a href=#101 id=101 data-nosnippet>101</a> |
| <a href=#102 id=102 data-nosnippet>102</a><span class="kw">impl </span>DiscoverProjectMessage { |
| <a href=#103 id=103 data-nosnippet>103</a> <span class="kw">fn </span>new(data: DiscoverProjectData) -> <span class="self">Self </span>{ |
| <a href=#104 id=104 data-nosnippet>104</a> <span class="kw">match </span>data { |
| <a href=#105 id=105 data-nosnippet>105</a> DiscoverProjectData::Finished { project, buildfile, .. } => { |
| <a href=#106 id=106 data-nosnippet>106</a> <span class="kw">let </span>buildfile = buildfile.try_into().expect(<span class="string">"Unable to make path absolute"</span>); |
| <a href=#107 id=107 data-nosnippet>107</a> DiscoverProjectMessage::Finished { project, buildfile } |
| <a href=#108 id=108 data-nosnippet>108</a> } |
| <a href=#109 id=109 data-nosnippet>109</a> DiscoverProjectData::Error { error, source } => { |
| <a href=#110 id=110 data-nosnippet>110</a> DiscoverProjectMessage::Error { error, source } |
| <a href=#111 id=111 data-nosnippet>111</a> } |
| <a href=#112 id=112 data-nosnippet>112</a> DiscoverProjectData::Progress { message } => { |
| <a href=#113 id=113 data-nosnippet>113</a> DiscoverProjectMessage::Progress { message } |
| <a href=#114 id=114 data-nosnippet>114</a> } |
| <a href=#115 id=115 data-nosnippet>115</a> } |
| <a href=#116 id=116 data-nosnippet>116</a> } |
| <a href=#117 id=117 data-nosnippet>117</a>} |
| <a href=#118 id=118 data-nosnippet>118</a> |
| <a href=#119 id=119 data-nosnippet>119</a><span class="kw">struct </span>DiscoverProjectParser; |
| <a href=#120 id=120 data-nosnippet>120</a> |
| <a href=#121 id=121 data-nosnippet>121</a><span class="kw">impl </span>JsonLinesParser<DiscoverProjectMessage> <span class="kw">for </span>DiscoverProjectParser { |
| <a href=#122 id=122 data-nosnippet>122</a> <span class="kw">fn </span>from_line(<span class="kw-2">&</span><span class="self">self</span>, line: <span class="kw-2">&</span>str, _error: <span class="kw-2">&mut </span>String) -> <span class="prelude-ty">Option</span><DiscoverProjectMessage> { |
| <a href=#123 id=123 data-nosnippet>123</a> <span class="kw">match </span>serde_json::from_str::<DiscoverProjectData>(line) { |
| <a href=#124 id=124 data-nosnippet>124</a> <span class="prelude-val">Ok</span>(data) => { |
| <a href=#125 id=125 data-nosnippet>125</a> <span class="kw">let </span>msg = DiscoverProjectMessage::new(data); |
| <a href=#126 id=126 data-nosnippet>126</a> <span class="prelude-val">Some</span>(msg) |
| <a href=#127 id=127 data-nosnippet>127</a> } |
| <a href=#128 id=128 data-nosnippet>128</a> <span class="prelude-val">Err</span>(err) => { |
| <a href=#129 id=129 data-nosnippet>129</a> <span class="kw">let </span>err = |
| <a href=#130 id=130 data-nosnippet>130</a> DiscoverProjectData::Error { error: <span class="macro">format!</span>(<span class="string">"{err:#?}\n{line}"</span>), source: <span class="prelude-val">None </span>}; |
| <a href=#131 id=131 data-nosnippet>131</a> <span class="prelude-val">Some</span>(DiscoverProjectMessage::new(err)) |
| <a href=#132 id=132 data-nosnippet>132</a> } |
| <a href=#133 id=133 data-nosnippet>133</a> } |
| <a href=#134 id=134 data-nosnippet>134</a> } |
| <a href=#135 id=135 data-nosnippet>135</a> |
| <a href=#136 id=136 data-nosnippet>136</a> <span class="kw">fn </span>from_eof(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="prelude-ty">Option</span><DiscoverProjectMessage> { |
| <a href=#137 id=137 data-nosnippet>137</a> <span class="prelude-val">None |
| <a href=#138 id=138 data-nosnippet>138</a> </span>} |
| <a href=#139 id=139 data-nosnippet>139</a>} |
| <a href=#140 id=140 data-nosnippet>140</a> |
| <a href=#141 id=141 data-nosnippet>141</a><span class="attr">#[test] |
| <a href=#142 id=142 data-nosnippet>142</a></span><span class="kw">fn </span>test_deserialization() { |
| <a href=#143 id=143 data-nosnippet>143</a> <span class="kw">let </span>message = <span class="string">r#" |
| <a href=#144 id=144 data-nosnippet>144</a> {"kind": "progress", "message":"querying build system","input":{"files":["src/main.rs"]}} |
| <a href=#145 id=145 data-nosnippet>145</a> "#</span>; |
| <a href=#146 id=146 data-nosnippet>146</a> <span class="kw">let </span>message: DiscoverProjectData = |
| <a href=#147 id=147 data-nosnippet>147</a> serde_json::from_str(message).expect(<span class="string">"Unable to deserialize message"</span>); |
| <a href=#148 id=148 data-nosnippet>148</a> <span class="macro">assert!</span>(<span class="macro">matches!</span>(message, DiscoverProjectData::Progress { .. })); |
| <a href=#149 id=149 data-nosnippet>149</a> |
| <a href=#150 id=150 data-nosnippet>150</a> <span class="kw">let </span>message = <span class="string">r#" |
| <a href=#151 id=151 data-nosnippet>151</a> {"kind": "error", "error":"failed to deserialize command output","source":"command"} |
| <a href=#152 id=152 data-nosnippet>152</a> "#</span>; |
| <a href=#153 id=153 data-nosnippet>153</a> |
| <a href=#154 id=154 data-nosnippet>154</a> <span class="kw">let </span>message: DiscoverProjectData = |
| <a href=#155 id=155 data-nosnippet>155</a> serde_json::from_str(message).expect(<span class="string">"Unable to deserialize message"</span>); |
| <a href=#156 id=156 data-nosnippet>156</a> <span class="macro">assert!</span>(<span class="macro">matches!</span>(message, DiscoverProjectData::Error { .. })); |
| <a href=#157 id=157 data-nosnippet>157</a> |
| <a href=#158 id=158 data-nosnippet>158</a> <span class="kw">let </span>message = <span class="string">r#" |
| <a href=#159 id=159 data-nosnippet>159</a> {"kind": "finished", "project": {"sysroot": "foo", "crates": [], "runnables": []}, "buildfile":"rust-analyzer/BUILD"} |
| <a href=#160 id=160 data-nosnippet>160</a> "#</span>; |
| <a href=#161 id=161 data-nosnippet>161</a> |
| <a href=#162 id=162 data-nosnippet>162</a> <span class="kw">let </span>message: DiscoverProjectData = |
| <a href=#163 id=163 data-nosnippet>163</a> serde_json::from_str(message).expect(<span class="string">"Unable to deserialize message"</span>); |
| <a href=#164 id=164 data-nosnippet>164</a> <span class="macro">assert!</span>(<span class="macro">matches!</span>(message, DiscoverProjectData::Finished { .. })); |
| <a href=#165 id=165 data-nosnippet>165</a>} |
| </code></pre></div></section></main></body></html> |
