1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
use crate::evaluate::expr::run_expression_block;
use crate::evaluate::internal::run_internal_command;
use crate::evaluation_context::EvaluationContext;
use nu_errors::ShellError;
use nu_parser::ParserScope;
use nu_protocol::hir::{
Block, Call, ClassifiedCommand, Expression, ExternalRedirection, Pipeline, SpannedExpression,
Synthetic,
};
use nu_protocol::{UntaggedValue, Value};
use nu_source::{Span, Tag};
use nu_stream::{InputStream, OutputStream};
use std::sync::atomic::Ordering;
pub fn run_block(
block: &Block,
ctx: &EvaluationContext,
mut input: InputStream,
external_redirection: ExternalRedirection,
) -> Result<OutputStream, ShellError> {
let mut output: Result<InputStream, ShellError> = Ok(OutputStream::empty());
for definition in block.definitions.values() {
ctx.scope.add_definition(definition.clone());
}
let num_groups = block.block.len();
for (group_num, group) in block.block.iter().enumerate() {
let num_pipelines = group.pipelines.len();
for (pipeline_num, pipeline) in group.pipelines.iter().enumerate() {
match output {
Ok(inp) if inp.is_empty() => {}
Ok(inp) => {
// Run autoview on the values we've seen so far
// We may want to make this configurable for other kinds of hosting
if let Some(autoview) = ctx.get_command("autoview") {
let mut output_stream = match ctx.run_command(
autoview,
Tag::unknown(),
Call::new(
Box::new(SpannedExpression::new(
Expression::Synthetic(Synthetic::String("autoview".into())),
Span::unknown(),
)),
Span::unknown(),
),
inp,
) {
Ok(x) => x,
Err(e) => {
return Err(e);
}
};
match output_stream.next() {
Some(Value {
value: UntaggedValue::Error(e),
..
}) => {
return Err(e);
}
Some(_item) => {
if let Some(err) = ctx.get_errors().get(0) {
ctx.clear_errors();
return Err(err.clone());
}
if ctx.ctrl_c().load(Ordering::SeqCst) {
return Ok(InputStream::empty());
}
}
None => {
if let Some(err) = ctx.get_errors().get(0) {
ctx.clear_errors();
return Err(err.clone());
}
}
}
} else {
let _: Vec<_> = inp.collect();
}
}
Err(e) => {
return Err(e);
}
}
output = Ok(OutputStream::empty());
match output {
Ok(inp) if inp.is_empty() => {}
Ok(mut output_stream) => {
match output_stream.next() {
Some(Value {
value: UntaggedValue::Error(e),
..
}) => {
return Err(e);
}
Some(_item) => {
if let Some(err) = ctx.get_errors().get(0) {
ctx.clear_errors();
return Err(err.clone());
}
if ctx.ctrl_c().load(Ordering::SeqCst) {
// This early return doesn't return the result
// we have so far, but breaking out of this loop
// causes lifetime issues. A future contribution
// could attempt to return the current output.
// https://github.com/nushell/nushell/pull/2830#discussion_r550319687
return Ok(InputStream::empty());
}
}
None => {
if let Some(err) = ctx.get_errors().get(0) {
ctx.clear_errors();
return Err(err.clone());
}
}
}
}
Err(e) => {
return Err(e);
}
}
output = if group_num == (num_groups - 1) && pipeline_num == (num_pipelines - 1) {
// we're at the end of the block, so use the given external redirection
run_pipeline(pipeline, ctx, input, external_redirection)
} else {
// otherwise, we're in the middle of the block, so use a default redirection
run_pipeline(pipeline, ctx, input, ExternalRedirection::None)
};
input = OutputStream::empty();
}
}
output
}
fn run_pipeline(
commands: &Pipeline,
ctx: &EvaluationContext,
mut input: InputStream,
external_redirection: ExternalRedirection,
) -> Result<OutputStream, ShellError> {
let num_commands = commands.list.len();
for (command_num, command) in commands.list.iter().enumerate() {
input = match command {
ClassifiedCommand::Dynamic(call) => {
let mut args = vec![];
if let Some(positional) = &call.positional {
for pos in positional {
let result = run_expression_block(pos, ctx)?.into_vec();
args.push(result);
}
}
let block = run_expression_block(&call.head, ctx)?.into_vec();
if block.len() != 1 {
return Err(ShellError::labeled_error(
"Dynamic commands must start with a block",
"needs to be a block",
call.head.span,
));
}
match &block[0].value {
UntaggedValue::Block(captured_block) => {
ctx.scope.enter_scope();
ctx.scope.add_vars(&captured_block.captured.entries);
for (param, value) in
captured_block.block.params.positional.iter().zip(&args)
{
ctx.scope.add_var(param.0.name(), value[0].clone());
}
let result =
run_block(&captured_block.block, ctx, input, external_redirection);
ctx.scope.exit_scope();
result?
}
_ => {
return Err(ShellError::labeled_error("Dynamic commands must start with a block (or variable pointing to a block)", "needs to be a block", call.head.span));
}
}
}
ClassifiedCommand::Expr(expr) => run_expression_block(expr, ctx)?,
ClassifiedCommand::Error(err) => return Err(err.clone().into()),
ClassifiedCommand::Internal(left) => {
if command_num == (num_commands - 1) {
let mut left = left.clone();
left.args.external_redirection = external_redirection;
run_internal_command(&left, ctx, input)?
} else {
run_internal_command(left, ctx, input)?
}
}
};
}
Ok(input)
}