nushell/crates/nu-engine/src/eval.rs
JT 2013e9300a
Make config default if broken (#482)
* Make config default if broken

* Make config default if broken
2021-12-13 14:16:51 +11:00

931 lines
31 KiB
Rust

use std::cmp::Ordering;
use nu_protocol::ast::{Block, Call, Expr, Expression, Operator, Statement};
use nu_protocol::engine::{EngineState, Stack};
use nu_protocol::{
IntoPipelineData, PipelineData, Range, ShellError, Span, Spanned, Type, Unit, Value, VarId,
};
use crate::get_full_help;
pub fn eval_operator(op: &Expression) -> Result<Operator, ShellError> {
match op {
Expression {
expr: Expr::Operator(operator),
..
} => Ok(operator.clone()),
Expression { span, expr, .. } => {
Err(ShellError::UnknownOperator(format!("{:?}", expr), *span))
}
}
}
fn eval_call(
engine_state: &EngineState,
stack: &mut Stack,
call: &Call,
input: PipelineData,
) -> Result<PipelineData, ShellError> {
let decl = engine_state.get_decl(call.decl_id);
if call.named.iter().any(|(flag, _)| flag.item == "help") {
let full_help = get_full_help(&decl.signature(), &decl.examples(), engine_state);
Ok(Value::String {
val: full_help,
span: call.head,
}
.into_pipeline_data())
} else if let Some(block_id) = decl.get_block_id() {
let block = engine_state.get_block(block_id);
let mut stack = stack.collect_captures(&block.captures);
for (arg, param) in call.positional.iter().zip(
decl.signature()
.required_positional
.iter()
.chain(decl.signature().optional_positional.iter()),
) {
let result = eval_expression(engine_state, &mut stack, arg)?;
let var_id = param
.var_id
.expect("internal error: all custom parameters must have var_ids");
stack.add_var(var_id, result);
}
if let Some(rest_positional) = decl.signature().rest_positional {
let mut rest_items = vec![];
for arg in call.positional.iter().skip(
decl.signature().required_positional.len()
+ decl.signature().optional_positional.len(),
) {
let result = eval_expression(engine_state, &mut stack, arg)?;
rest_items.push(result);
}
let span = if let Some(rest_item) = rest_items.first() {
rest_item.span()?
} else {
Span::unknown()
};
stack.add_var(
rest_positional
.var_id
.expect("Internal error: rest positional parameter lacks var_id"),
Value::List {
vals: rest_items,
span,
},
)
}
for named in decl.signature().named {
if let Some(var_id) = named.var_id {
let mut found = false;
for call_named in &call.named {
if call_named.0.item == named.long {
if let Some(arg) = &call_named.1 {
let result = eval_expression(engine_state, &mut stack, arg)?;
stack.add_var(var_id, result);
} else {
stack.add_var(
var_id,
Value::Bool {
val: true,
span: call.head,
},
)
}
found = true;
}
}
if !found && named.arg.is_none() {
stack.add_var(
var_id,
Value::Bool {
val: false,
span: call.head,
},
)
}
}
}
eval_block(engine_state, &mut stack, block, input)
} else {
decl.run(engine_state, stack, call, input)
}
}
fn eval_external(
engine_state: &EngineState,
stack: &mut Stack,
name: &str,
name_span: &Span,
args: &[Expression],
input: PipelineData,
last_expression: bool,
) -> Result<PipelineData, ShellError> {
let decl_id = engine_state
.find_decl("run_external".as_bytes())
.ok_or_else(|| ShellError::ExternalNotSupported(*name_span))?;
let command = engine_state.get_decl(decl_id);
let mut call = Call::new();
call.positional.push(Expression {
expr: Expr::String(name.trim_start_matches('^').to_string()),
span: *name_span,
ty: Type::String,
custom_completion: None,
});
for arg in args {
call.positional.push(arg.clone())
}
if last_expression {
call.named.push((
Spanned {
item: "last_expression".into(),
span: Span::unknown(),
},
None,
))
}
command.run(engine_state, stack, &call, input)
}
pub fn eval_expression(
engine_state: &EngineState,
stack: &mut Stack,
expr: &Expression,
) -> Result<Value, ShellError> {
match &expr.expr {
Expr::Bool(b) => Ok(Value::Bool {
val: *b,
span: expr.span,
}),
Expr::Int(i) => Ok(Value::Int {
val: *i,
span: expr.span,
}),
Expr::Float(f) => Ok(Value::Float {
val: *f,
span: expr.span,
}),
Expr::ValueWithUnit(e, unit) => match eval_expression(engine_state, stack, e)? {
Value::Int { val, .. } => Ok(compute(val, unit.item, unit.span)),
x => Err(ShellError::CantConvert(
"unit value".into(),
x.get_type().to_string(),
e.span,
)),
},
Expr::Range(from, next, to, operator) => {
let from = if let Some(f) = from {
eval_expression(engine_state, stack, f)?
} else {
Value::Nothing {
span: Span::unknown(),
}
};
let next = if let Some(s) = next {
eval_expression(engine_state, stack, s)?
} else {
Value::Nothing {
span: Span::unknown(),
}
};
let to = if let Some(t) = to {
eval_expression(engine_state, stack, t)?
} else {
Value::Nothing {
span: Span::unknown(),
}
};
Ok(Value::Range {
val: Box::new(Range::new(expr.span, from, next, to, operator)?),
span: expr.span,
})
}
Expr::Var(var_id) => eval_variable(engine_state, stack, *var_id, expr.span),
Expr::VarDecl(_) => Ok(Value::Nothing { span: expr.span }),
Expr::CellPath(cell_path) => Ok(Value::CellPath {
val: cell_path.clone(),
span: expr.span,
}),
Expr::FullCellPath(cell_path) => {
let value = eval_expression(engine_state, stack, &cell_path.head)?;
value.follow_cell_path(&cell_path.tail)
}
Expr::ImportPattern(_) => Ok(Value::Nothing {
span: Span::unknown(),
}),
Expr::Call(call) => {
// FIXME: protect this collect with ctrl-c
Ok(
eval_call(engine_state, stack, call, PipelineData::new(call.head))?
.into_value(call.head),
)
}
Expr::ExternalCall(name, span, args) => {
// FIXME: protect this collect with ctrl-c
Ok(eval_external(
engine_state,
stack,
name,
span,
args,
PipelineData::new(*span),
true,
)?
.into_value(*span))
}
Expr::Operator(_) => Ok(Value::Nothing { span: expr.span }),
Expr::BinaryOp(lhs, op, rhs) => {
let op_span = op.span;
let lhs = eval_expression(engine_state, stack, lhs)?;
let op = eval_operator(op)?;
let rhs = eval_expression(engine_state, stack, rhs)?;
match op {
Operator::Plus => lhs.add(op_span, &rhs),
Operator::Minus => lhs.sub(op_span, &rhs),
Operator::Multiply => lhs.mul(op_span, &rhs),
Operator::Divide => lhs.div(op_span, &rhs),
Operator::LessThan => lhs.lt(op_span, &rhs),
Operator::LessThanOrEqual => lhs.lte(op_span, &rhs),
Operator::GreaterThan => lhs.gt(op_span, &rhs),
Operator::GreaterThanOrEqual => lhs.gte(op_span, &rhs),
Operator::Equal => lhs.eq(op_span, &rhs),
Operator::NotEqual => lhs.ne(op_span, &rhs),
Operator::In => lhs.r#in(op_span, &rhs),
Operator::NotIn => lhs.not_in(op_span, &rhs),
Operator::Contains => lhs.contains(op_span, &rhs),
Operator::NotContains => lhs.not_contains(op_span, &rhs),
Operator::Modulo => lhs.modulo(op_span, &rhs),
Operator::And => lhs.and(op_span, &rhs),
Operator::Or => lhs.or(op_span, &rhs),
Operator::Pow => lhs.pow(op_span, &rhs),
}
}
Expr::RowCondition(block_id) | Expr::Subexpression(block_id) => {
let block = engine_state.get_block(*block_id);
// FIXME: protect this collect with ctrl-c
Ok(
eval_subexpression(engine_state, stack, block, PipelineData::new(expr.span))?
.into_value(expr.span),
)
}
Expr::Block(block_id) => Ok(Value::Block {
val: *block_id,
span: expr.span,
}),
Expr::List(x) => {
let mut output = vec![];
for expr in x {
output.push(eval_expression(engine_state, stack, expr)?);
}
Ok(Value::List {
vals: output,
span: expr.span,
})
}
Expr::Record(fields) => {
let mut cols = vec![];
let mut vals = vec![];
for (col, val) in fields {
cols.push(eval_expression(engine_state, stack, col)?.as_string()?);
vals.push(eval_expression(engine_state, stack, val)?);
}
Ok(Value::Record {
cols,
vals,
span: expr.span,
})
}
Expr::Table(headers, vals) => {
let mut output_headers = vec![];
for expr in headers {
output_headers.push(eval_expression(engine_state, stack, expr)?.as_string()?);
}
let mut output_rows = vec![];
for val in vals {
let mut row = vec![];
for expr in val {
row.push(eval_expression(engine_state, stack, expr)?);
}
output_rows.push(Value::Record {
cols: output_headers.clone(),
vals: row,
span: expr.span,
});
}
Ok(Value::List {
vals: output_rows,
span: expr.span,
})
}
Expr::Keyword(_, _, expr) => eval_expression(engine_state, stack, expr),
Expr::String(s) => Ok(Value::String {
val: s.clone(),
span: expr.span,
}),
Expr::Filepath(s) => Ok(Value::String {
val: s.clone(),
span: expr.span,
}),
Expr::GlobPattern(s) => Ok(Value::String {
val: s.clone(),
span: expr.span,
}),
Expr::Signature(_) => Ok(Value::Nothing { span: expr.span }),
Expr::Garbage => Ok(Value::Nothing { span: expr.span }),
}
}
pub fn eval_block(
engine_state: &EngineState,
stack: &mut Stack,
block: &Block,
mut input: PipelineData,
) -> Result<PipelineData, ShellError> {
for stmt in block.stmts.iter() {
if let Statement::Pipeline(pipeline) = stmt {
for (i, elem) in pipeline.expressions.iter().enumerate() {
match elem {
Expression {
expr: Expr::Call(call),
..
} => {
input = eval_call(engine_state, stack, call, input)?;
}
Expression {
expr: Expr::ExternalCall(name, name_span, args),
..
} => {
input = eval_external(
engine_state,
stack,
name,
name_span,
args,
input,
i == pipeline.expressions.len() - 1,
)?;
}
elem => {
input = eval_expression(engine_state, stack, elem)?.into_pipeline_data();
}
}
}
}
}
Ok(input)
}
pub fn eval_subexpression(
engine_state: &EngineState,
stack: &mut Stack,
block: &Block,
mut input: PipelineData,
) -> Result<PipelineData, ShellError> {
for stmt in block.stmts.iter() {
if let Statement::Pipeline(pipeline) = stmt {
for (i, elem) in pipeline.expressions.iter().enumerate() {
match elem {
Expression {
expr: Expr::Call(call),
..
} => {
input = eval_call(engine_state, stack, call, input)?;
}
Expression {
expr: Expr::ExternalCall(name, name_span, args),
..
} => {
input = eval_external(
engine_state,
stack,
name,
name_span,
args,
input,
false,
)?;
if i == pipeline.expressions.len() - 1 {
// We're at the end, so drain as a string for the value
// to be used later
// FIXME: the trimming of the end probably needs to live in a better place
let config = stack.get_config().unwrap_or_default();
let mut s = input.collect_string("", &config);
if s.ends_with('\n') {
s.pop();
}
input = Value::String {
val: s.to_string(),
span: *name_span,
}
.into_pipeline_data()
}
}
elem => {
input = eval_expression(engine_state, stack, elem)?.into_pipeline_data();
}
}
}
}
}
Ok(input)
}
pub fn eval_variable(
engine_state: &EngineState,
stack: &Stack,
var_id: VarId,
span: Span,
) -> Result<Value, ShellError> {
if var_id == nu_protocol::NU_VARIABLE_ID {
// $nu
let mut output_cols = vec![];
let mut output_vals = vec![];
let env_vars = stack.get_env_vars();
let env_columns: Vec<_> = env_vars.keys().map(|x| x.to_string()).collect();
let env_values: Vec<_> = env_vars
.values()
.map(|x| Value::String {
val: x.to_string(),
span,
})
.collect();
output_cols.push("env".into());
output_vals.push(Value::Record {
cols: env_columns,
vals: env_values,
span,
});
if let Some(mut config_path) = nu_path::config_dir() {
config_path.push("nushell");
let mut history_path = config_path.clone();
let mut keybinding_path = config_path.clone();
history_path.push("history.txt");
output_cols.push("history-path".into());
output_vals.push(Value::String {
val: history_path.to_string_lossy().to_string(),
span,
});
config_path.push("config.nu");
output_cols.push("config-path".into());
output_vals.push(Value::String {
val: config_path.to_string_lossy().to_string(),
span,
});
// TODO: keybindings don't exist yet but lets add a file
// path for them to be stored in. It doesn't have to be yml.
keybinding_path.push("keybindings.yml");
output_cols.push("keybinding-path".into());
output_vals.push(Value::String {
val: keybinding_path.to_string_lossy().to_string(),
span,
})
}
#[cfg(feature = "plugin")]
if let Some(path) = &engine_state.plugin_signatures {
if let Some(path_str) = path.to_str() {
output_cols.push("plugin-path".into());
output_vals.push(Value::String {
val: path_str.into(),
span,
});
}
}
// since the env var PWD doesn't exist on all platforms
// lets just get the current directory
if let Ok(current_dir) = std::env::current_dir() {
if let Some(cwd) = current_dir.to_str() {
output_cols.push("cwd".into());
output_vals.push(Value::String {
val: cwd.into(),
span,
})
}
}
if let Some(home_path) = nu_path::home_dir() {
if let Some(home_path_str) = home_path.to_str() {
output_cols.push("home-path".into());
output_vals.push(Value::String {
val: home_path_str.into(),
span,
})
}
}
let temp = std::env::temp_dir();
if let Some(temp_path) = temp.to_str() {
output_cols.push("temp-path".into());
output_vals.push(Value::String {
val: temp_path.into(),
span,
})
}
Ok(Value::Record {
cols: output_cols,
vals: output_vals,
span,
})
} else if var_id == nu_protocol::SCOPE_VARIABLE_ID {
let mut output_cols = vec![];
let mut output_vals = vec![];
let mut var_names = vec![];
let mut var_types = vec![];
let mut commands = vec![];
let mut aliases = vec![];
let mut overlays = vec![];
for frame in &engine_state.scope {
for var in &frame.vars {
var_names.push(String::from_utf8_lossy(var.0).to_string());
let var = engine_state.get_var(*var.1);
var_types.push(Value::string(var.to_string(), span));
}
for command in &frame.decls {
let mut cols = vec![];
let mut vals = vec![];
cols.push("command".into());
vals.push(Value::String {
val: String::from_utf8_lossy(command.0).to_string(),
span,
});
let decl = engine_state.get_decl(*command.1);
let signature = decl.signature();
cols.push("category".to_string());
vals.push(Value::String {
val: signature.category.to_string(),
span,
});
// signature
let mut sig_records = vec![];
{
let sig_cols = vec![
"command".to_string(),
"parameter_name".to_string(),
"parameter_type".to_string(),
"syntax_shape".to_string(),
"is_optional".to_string(),
"short_flag".to_string(),
"description".to_string(),
];
// required_positional
for req in signature.required_positional {
let sig_vals = vec![
Value::string(&signature.name, span),
Value::string(req.name, span),
Value::string("positional", span),
Value::string(req.shape.to_type().to_string(), span),
Value::boolean(false, span),
Value::nothing(span),
Value::string(req.desc, span),
];
sig_records.push(Value::Record {
cols: sig_cols.clone(),
vals: sig_vals,
span,
});
}
// optional_positional
for opt in signature.optional_positional {
let sig_vals = vec![
Value::string(&signature.name, span),
Value::string(opt.name, span),
Value::string("positional", span),
Value::string(opt.shape.to_type().to_string(), span),
Value::boolean(true, span),
Value::nothing(span),
Value::string(opt.desc, span),
];
sig_records.push(Value::Record {
cols: sig_cols.clone(),
vals: sig_vals,
span,
});
}
{
// rest_positional
let (name, shape, desc) = if let Some(rest) = signature.rest_positional {
(
Value::string(rest.name, span),
Value::string(rest.shape.to_type().to_string(), span),
Value::string(rest.desc, span),
)
} else {
(
Value::nothing(span),
Value::nothing(span),
Value::nothing(span),
)
};
let sig_vals = vec![
Value::string(&signature.name, span),
name,
Value::string("rest", span),
shape,
Value::boolean(false, span),
Value::nothing(span),
desc,
];
sig_records.push(Value::Record {
cols: sig_cols.clone(),
vals: sig_vals,
span,
});
}
// named flags
for named in signature.named {
let shape = if let Some(arg) = named.arg {
Value::string(arg.to_type().to_string(), span)
} else {
Value::nothing(span)
};
let short_flag = if let Some(c) = named.short {
Value::string(c, span)
} else {
Value::nothing(span)
};
let sig_vals = vec![
Value::string(&signature.name, span),
Value::string(named.long, span),
Value::string("named", span),
shape,
Value::boolean(!named.required, span),
short_flag,
Value::string(named.desc, span),
];
sig_records.push(Value::Record {
cols: sig_cols.clone(),
vals: sig_vals,
span,
});
}
}
cols.push("signature".to_string());
vals.push(Value::List {
vals: sig_records,
span,
});
cols.push("usage".to_string());
vals.push(Value::String {
val: decl.usage().into(),
span,
});
cols.push("is_binary".to_string());
vals.push(Value::Bool {
val: decl.is_binary(),
span,
});
cols.push("is_private".to_string());
vals.push(Value::Bool {
val: decl.is_private(),
span,
});
cols.push("is_builtin".to_string());
vals.push(Value::Bool {
val: decl.is_builtin(),
span,
});
cols.push("is_sub".to_string());
vals.push(Value::Bool {
val: decl.is_sub(),
span,
});
cols.push("is_plugin".to_string());
vals.push(Value::Bool {
val: decl.is_plugin().is_some(),
span,
});
cols.push("is_custom".to_string());
vals.push(Value::Bool {
val: decl.get_block_id().is_some(),
span,
});
cols.push("creates_scope".to_string());
vals.push(Value::Bool {
val: signature.creates_scope,
span,
});
cols.push("extra_usage".to_string());
vals.push(Value::String {
val: decl.extra_usage().into(),
span,
});
commands.push(Value::Record { cols, vals, span })
}
for alias in &frame.aliases {
aliases.push(Value::String {
val: String::from_utf8_lossy(alias.0).to_string(),
span,
});
}
for overlay in &frame.overlays {
overlays.push(Value::String {
val: String::from_utf8_lossy(overlay.0).to_string(),
span,
});
}
}
output_cols.push("vars".to_string());
output_vals.push(Value::Record {
cols: var_names,
vals: var_types,
span,
});
commands.sort_by(|a, b| match (a, b) {
(Value::Record { vals: rec_a, .. }, Value::Record { vals: rec_b, .. }) => {
// Comparing the first value from the record
// It is expected that the first value is the name of the column
// The names of the commands should be a value string
match (rec_a.get(0), rec_b.get(0)) {
(Some(val_a), Some(val_b)) => match (val_a, val_b) {
(Value::String { val: str_a, .. }, Value::String { val: str_b, .. }) => {
str_a.cmp(str_b)
}
_ => Ordering::Equal,
},
_ => Ordering::Equal,
}
}
_ => Ordering::Equal,
});
output_cols.push("commands".to_string());
output_vals.push(Value::List {
vals: commands,
span,
});
aliases.sort_by(|a, b| a.partial_cmp(b).unwrap_or(Ordering::Equal));
output_cols.push("aliases".to_string());
output_vals.push(Value::List {
vals: aliases,
span,
});
overlays.sort_by(|a, b| a.partial_cmp(b).unwrap_or(Ordering::Equal));
output_cols.push("overlays".to_string());
output_vals.push(Value::List {
vals: overlays,
span,
});
Ok(Value::Record {
cols: output_cols,
vals: output_vals,
span,
})
} else {
stack
.get_var(var_id)
.map_err(move |_| ShellError::VariableNotFoundAtRuntime(span))
}
}
pub fn compute(size: i64, unit: Unit, span: Span) -> Value {
match unit {
Unit::Byte => Value::Filesize { val: size, span },
Unit::Kilobyte => Value::Filesize {
val: size * 1000,
span,
},
Unit::Megabyte => Value::Filesize {
val: size * 1000 * 1000,
span,
},
Unit::Gigabyte => Value::Filesize {
val: size * 1000 * 1000 * 1000,
span,
},
Unit::Terabyte => Value::Filesize {
val: size * 1000 * 1000 * 1000 * 1000,
span,
},
Unit::Petabyte => Value::Filesize {
val: size * 1000 * 1000 * 1000 * 1000 * 1000,
span,
},
Unit::Kibibyte => Value::Filesize {
val: size * 1024,
span,
},
Unit::Mebibyte => Value::Filesize {
val: size * 1024 * 1024,
span,
},
Unit::Gibibyte => Value::Filesize {
val: size * 1024 * 1024 * 1024,
span,
},
Unit::Tebibyte => Value::Filesize {
val: size * 1024 * 1024 * 1024 * 1024,
span,
},
Unit::Pebibyte => Value::Filesize {
val: size * 1024 * 1024 * 1024 * 1024 * 1024,
span,
},
Unit::Nanosecond => Value::Duration { val: size, span },
Unit::Microsecond => Value::Duration {
val: size * 1000,
span,
},
Unit::Millisecond => Value::Duration {
val: size * 1000 * 1000,
span,
},
Unit::Second => Value::Duration {
val: size * 1000 * 1000 * 1000,
span,
},
Unit::Minute => Value::Duration {
val: size * 1000 * 1000 * 1000 * 60,
span,
},
Unit::Hour => Value::Duration {
val: size * 1000 * 1000 * 1000 * 60 * 60,
span,
},
Unit::Day => Value::Duration {
val: size * 1000 * 1000 * 1000 * 60 * 60 * 24,
span,
},
Unit::Week => Value::Duration {
val: size * 1000 * 1000 * 1000 * 60 * 60 * 24 * 7,
span,
},
}
}