starts_with ends_with match functions for string (#2269)

crates/nu-cli/src/cli.rs

@@ -313,6 +313,8 @@ pub fn create_default_context(
             whole_stream_command(StrTrim),
             whole_stream_command(StrTrimLeft),
             whole_stream_command(StrTrimRight),
+            whole_stream_command(StrStartsWith),
+            whole_stream_command(StrEndsWith),
             whole_stream_command(StrCollect),
             whole_stream_command(StrLength),
             whole_stream_command(StrReverse),

crates/nu-cli/src/commands.rs

@@ -229,9 +229,9 @@ pub(crate) use sort_by::SortBy;
 pub(crate) use split::{Split, SplitChars, SplitColumn, SplitRow};
 pub(crate) use split_by::SplitBy;
 pub(crate) use str_::{
-    Str, StrCapitalize, StrCollect, StrDowncase, StrFindReplace, StrFrom, StrLength, StrReverse,
-    StrSet, StrSubstring, StrToDatetime, StrToDecimal, StrToInteger, StrTrim, StrTrimLeft,
-    StrTrimRight, StrUpcase,
+    Str, StrCapitalize, StrCollect, StrDowncase, StrEndsWith, StrFindReplace, StrFrom, StrLength,
+    StrReverse, StrSet, StrStartsWith, StrSubstring, StrToDatetime, StrToDecimal, StrToInteger,
+    StrTrim, StrTrimLeft, StrTrimRight, StrUpcase,
 };
 pub(crate) use table::Table;
 pub(crate) use tags::Tags;

crates/nu-cli/src/commands/str_/ends_with.rs

@@ -0,0 +1,138 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::ShellTypeName;
+use nu_protocol::{
+    ColumnPath, Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
+};
+use nu_source::{Tag, Tagged};
+use nu_value_ext::ValueExt;
+
+#[derive(Deserialize)]
+struct Arguments {
+    pattern: Tagged<String>,
+    rest: Vec<ColumnPath>,
+}
+pub struct SubCommand;
+
+#[async_trait]
+impl WholeStreamCommand for SubCommand {
+    fn name(&self) -> &str {
+        "str ends-with"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("str ends-with")
+            .required("pattern", SyntaxShape::String, "the pattern to match")
+            .rest(
+                SyntaxShape::ColumnPath,
+                "optionally matches suffix of text by column paths",
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "checks if string ends with pattern"
+    }
+
+    async fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        operate(args, registry).await
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Checks if string ends with '.rb' pattern",
+            example: "echo 'my_library.rb' | str ends-with '.rb'",
+            result: Some(vec![UntaggedValue::boolean(true).into_untagged_value()]),
+        }]
+    }
+}
+
+async fn operate(
+    args: CommandArgs,
+    registry: &CommandRegistry,
+) -> Result<OutputStream, ShellError> {
+    let registry = registry.clone();
+
+    let (Arguments { pattern, rest }, input) = args.process(&registry).await?;
+
+    let column_paths: Vec<_> = rest;
+
+    Ok(input
+        .map(move |v| {
+            if column_paths.is_empty() {
+                ReturnSuccess::value(action(&v, &pattern, v.tag())?)
+            } else {
+                let mut ret = v;
+
+                for path in &column_paths {
+                    let pattern = pattern.clone();
+                    ret = ret.swap_data_by_column_path(
+                        path,
+                        Box::new(move |old| action(old, &pattern, old.tag())),
+                    )?;
+                }
+
+                ReturnSuccess::value(ret)
+            }
+        })
+        .to_output_stream())
+}
+
+fn action(input: &Value, pattern: &str, tag: impl Into<Tag>) -> Result<Value, ShellError> {
+    match &input.value {
+        UntaggedValue::Primitive(Primitive::Line(s))
+        | UntaggedValue::Primitive(Primitive::String(s)) => {
+            let ends_with = s.ends_with(pattern);
+            Ok(UntaggedValue::boolean(ends_with).into_value(tag))
+        }
+        other => {
+            let got = format!("got {}", other.type_name());
+            Err(ShellError::labeled_error(
+                "value is not string",
+                got,
+                tag.into().span,
+            ))
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{action, SubCommand};
+    use nu_plugin::test_helpers::value::string;
+    use nu_protocol::{Primitive, UntaggedValue};
+    use nu_source::Tag;
+
+    #[test]
+    fn examples_work_as_expected() {
+        use crate::examples::test as test_examples;
+
+        test_examples(SubCommand {})
+    }
+
+    #[test]
+    fn str_ends_with_pattern() {
+        let word = string("Cargo.toml");
+        let pattern = ".toml";
+        let expected =
+            UntaggedValue::Primitive(Primitive::Boolean(true.into())).into_untagged_value();
+
+        let actual = action(&word, &pattern, Tag::unknown()).unwrap();
+        assert_eq!(actual, expected);
+    }
+
+    #[test]
+    fn str_does_not_end_with_pattern() {
+        let word = string("Cargo.toml");
+        let pattern = "Car";
+        let expected =
+            UntaggedValue::Primitive(Primitive::Boolean(false.into())).into_untagged_value();
+
+        let actual = action(&word, &pattern, Tag::unknown()).unwrap();
+        assert_eq!(actual, expected);
+    }
+}

crates/nu-cli/src/commands/str_/mod.rs

@@ -2,11 +2,13 @@ mod capitalize;
 mod collect;
 mod command;
 mod downcase;
+mod ends_with;
 mod find_replace;
 mod from;
 mod length;
 mod reverse;
 mod set;
+mod starts_with;
 mod substring;
 mod to_datetime;
 mod to_decimal;
@@ -18,11 +20,13 @@ pub use capitalize::SubCommand as StrCapitalize;
 pub use collect::SubCommand as StrCollect;
 pub use command::Command as Str;
 pub use downcase::SubCommand as StrDowncase;
+pub use ends_with::SubCommand as StrEndsWith;
 pub use find_replace::SubCommand as StrFindReplace;
 pub use from::SubCommand as StrFrom;
 pub use length::SubCommand as StrLength;
 pub use reverse::SubCommand as StrReverse;
 pub use set::SubCommand as StrSet;
+pub use starts_with::SubCommand as StrStartsWith;
 pub use substring::SubCommand as StrSubstring;
 pub use to_datetime::SubCommand as StrToDatetime;
 pub use to_decimal::SubCommand as StrToDecimal;

crates/nu-cli/src/commands/str_/starts_with.rs

@@ -0,0 +1,138 @@
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::ShellTypeName;
+use nu_protocol::{
+    ColumnPath, Primitive, ReturnSuccess, Signature, SyntaxShape, UntaggedValue, Value,
+};
+use nu_source::{Tag, Tagged};
+use nu_value_ext::ValueExt;
+
+#[derive(Deserialize)]
+struct Arguments {
+    pattern: Tagged<String>,
+    rest: Vec<ColumnPath>,
+}
+pub struct SubCommand;
+
+#[async_trait]
+impl WholeStreamCommand for SubCommand {
+    fn name(&self) -> &str {
+        "str starts-with"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("str starts-with")
+            .required("pattern", SyntaxShape::String, "the pattern to match")
+            .rest(
+                SyntaxShape::ColumnPath,
+                "optionally matches prefix of text by column paths",
+            )
+    }
+
+    fn usage(&self) -> &str {
+        "checks if string starts with pattern"
+    }
+
+    async fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        operate(args, registry).await
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Checks if string starts with 'my' pattern",
+            example: "echo 'my_library.rb' | str starts-with 'my'",
+            result: Some(vec![UntaggedValue::boolean(true).into_untagged_value()]),
+        }]
+    }
+}
+
+async fn operate(
+    args: CommandArgs,
+    registry: &CommandRegistry,
+) -> Result<OutputStream, ShellError> {
+    let registry = registry.clone();
+
+    let (Arguments { pattern, rest }, input) = args.process(&registry).await?;
+
+    let column_paths: Vec<_> = rest;
+
+    Ok(input
+        .map(move |v| {
+            if column_paths.is_empty() {
+                ReturnSuccess::value(action(&v, &pattern, v.tag())?)
+            } else {
+                let mut ret = v;
+
+                for path in &column_paths {
+                    let pattern = pattern.clone();
+                    ret = ret.swap_data_by_column_path(
+                        path,
+                        Box::new(move |old| action(old, &pattern, old.tag())),
+                    )?;
+                }
+
+                ReturnSuccess::value(ret)
+            }
+        })
+        .to_output_stream())
+}
+
+fn action(input: &Value, pattern: &str, tag: impl Into<Tag>) -> Result<Value, ShellError> {
+    match &input.value {
+        UntaggedValue::Primitive(Primitive::Line(s))
+        | UntaggedValue::Primitive(Primitive::String(s)) => {
+            let starts_with = s.starts_with(pattern);
+            Ok(UntaggedValue::boolean(starts_with).into_value(tag))
+        }
+        other => {
+            let got = format!("got {}", other.type_name());
+            Err(ShellError::labeled_error(
+                "value is not string",
+                got,
+                tag.into().span,
+            ))
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{action, SubCommand};
+    use nu_plugin::test_helpers::value::string;
+    use nu_protocol::{Primitive, UntaggedValue};
+    use nu_source::Tag;
+
+    #[test]
+    fn examples_work_as_expected() {
+        use crate::examples::test as test_examples;
+
+        test_examples(SubCommand {})
+    }
+
+    #[test]
+    fn str_starts_with_pattern() {
+        let word = string("Cargo.toml");
+        let pattern = "Car";
+        let expected =
+            UntaggedValue::Primitive(Primitive::Boolean(true.into())).into_untagged_value();
+
+        let actual = action(&word, &pattern, Tag::unknown()).unwrap();
+        assert_eq!(actual, expected);
+    }
+
+    #[test]
+    fn str_does_not_start_with_pattern() {
+        let word = string("Cargo.toml");
+        let pattern = ".toml";
+        let expected =
+            UntaggedValue::Primitive(Primitive::Boolean(false.into())).into_untagged_value();
+
+        let actual = action(&word, &pattern, Tag::unknown()).unwrap();
+        assert_eq!(actual, expected);
+    }
+}