nu_command/env/
source_env.rs

1use nu_engine::{
2    command_prelude::*, find_in_dirs_env, get_dirs_var_from_call, get_eval_block_with_early_return,
3    redirect_env,
4};
5use nu_protocol::{
6    BlockId,
7    engine::CommandType,
8    shell_error::{self, io::IoError},
9};
10use std::path::PathBuf;
11
12/// Source a file for environment variables.
13#[derive(Clone)]
14pub struct SourceEnv;
15
16impl Command for SourceEnv {
17    fn name(&self) -> &str {
18        "source-env"
19    }
20
21    fn signature(&self) -> Signature {
22        Signature::build("source-env")
23            .input_output_types(vec![(Type::Any, Type::Any)])
24            .param(Parameter::Required(
25                PositionalArg::new(
26                    "filename",
27                    // type is string to avoid automatically canonicalizing the path
28                    SyntaxShape::OneOf(vec![SyntaxShape::String, SyntaxShape::Nothing]),
29                )
30                .desc("The filepath to the script file to source the environment from (`null` for no-op).")
31                .completion(Completion::Builtin(BuiltinCompletion::NuFile {
32                    std_virtual_path: false,
33                })),
34            ))
35            .category(Category::Core)
36    }
37
38    fn description(&self) -> &str {
39        "Source the environment from a source file into the current environment."
40    }
41
42    fn extra_description(&self) -> &str {
43        "This command is a parser keyword. For details, check:
44  https://www.nushell.sh/book/thinking_in_nu.html"
45    }
46
47    fn command_type(&self) -> CommandType {
48        CommandType::Keyword
49    }
50
51    fn run(
52        &self,
53        engine_state: &EngineState,
54        caller_stack: &mut Stack,
55        call: &Call,
56        input: PipelineData,
57    ) -> Result<PipelineData, ShellError> {
58        if call.get_parser_info(caller_stack, "noop").is_some() {
59            return Ok(PipelineData::empty());
60        }
61
62        let source_filename: Spanned<String> = call.req(engine_state, caller_stack, 0)?;
63
64        // Note: this hidden positional is the block_id that corresponded to the 0th position
65        // it is put here by the parser
66        let block_id: i64 = call.req_parser_info(engine_state, caller_stack, "block_id")?;
67        let block_id = BlockId::new(block_id as usize);
68
69        // Set the currently evaluated directory (file-relative PWD)
70        let file_path = if let Some(path) = find_in_dirs_env(
71            &source_filename.item,
72            engine_state,
73            caller_stack,
74            get_dirs_var_from_call(caller_stack, call),
75        )? {
76            PathBuf::from(&path)
77        } else {
78            return Err(ShellError::Io(IoError::new(
79                shell_error::io::ErrorKind::FileNotFound,
80                source_filename.span,
81                PathBuf::from(source_filename.item),
82            )));
83        };
84
85        if let Some(parent) = file_path.parent() {
86            let file_pwd = Value::string(parent.to_string_lossy(), call.head);
87
88            caller_stack.add_env_var("FILE_PWD".to_string(), file_pwd);
89        }
90
91        caller_stack.add_env_var(
92            "CURRENT_FILE".to_string(),
93            Value::string(file_path.to_string_lossy(), call.head),
94        );
95
96        // Evaluate the block
97        let block = engine_state.get_block(block_id).clone();
98        let mut callee_stack = caller_stack
99            .gather_captures(engine_state, &block.captures)
100            .reset_pipes();
101
102        let eval_block_with_early_return = get_eval_block_with_early_return(engine_state);
103
104        let result = eval_block_with_early_return(engine_state, &mut callee_stack, &block, input)
105            .map(|p| p.body);
106
107        // Merge the block's environment to the current stack
108        redirect_env(engine_state, caller_stack, &callee_stack);
109
110        // Remove the file-relative PWD
111        caller_stack.remove_env_var(engine_state, "FILE_PWD");
112        caller_stack.remove_env_var(engine_state, "CURRENT_FILE");
113
114        result
115    }
116
117    fn examples(&self) -> Vec<Example<'_>> {
118        vec![
119            Example {
120                description: "Sources the environment from foo.nu in the current context.",
121                example: "source-env foo.nu",
122                result: None,
123            },
124            Example {
125                description: "Sourcing `null` is a no-op.",
126                example: "source-env null",
127                result: None,
128            },
129        ]
130    }
131}
nu_command/env/source_env.rs

nu_command/env/
source_env.rs
