feat: update: #4518, Add example for register,source,save,shuffle and from tsv (#4577)

crates/nu-command/src/core_commands/register.rs

@@ -1,6 +1,6 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Category, PipelineData, Signature, SyntaxShape};
+use nu_protocol::{Category, Example, PipelineData, Signature, SyntaxShape};
 
 #[derive(Clone)]
 pub struct Register;
@@ -50,4 +50,19 @@ impl Command for Register {
     ) -> Result<nu_protocol::PipelineData, nu_protocol::ShellError> {
         Ok(PipelineData::new(call.head))
     }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Register `nu_plugin_extra_query` plugin from ~/.cargo/bin/ dir",
+                example: r#"register -e capnp ~/.cargo/bin/nu_plugin_extra_query"#,
+                result: None,
+            },
+            Example {
+                description: "Register `nu_plugin_extra_query` plugin from `nu -c`(plugin will be available in that nu session only)",
+                example: r#"let plugin = ((which nu).path.0 | path dirname | path join 'nu_plugin_extra_query'); nu -c $'register -e capnp ($plugin); version'"#,
+                result: None,
+            },
+        ]
+    }
 }

crates/nu-command/src/core_commands/source.rs

@@ -1,7 +1,7 @@
 use nu_engine::{eval_block, CallExt};
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Category, PipelineData, ShellError, Signature, SyntaxShape};
+use nu_protocol::{Category, Example, PipelineData, ShellError, Signature, SyntaxShape};
 
 /// Source a file for environment variables.
 #[derive(Clone)]
@@ -40,4 +40,24 @@ impl Command for Source {
         let block = engine_state.get_block(block_id as usize).clone();
         eval_block(engine_state, stack, &block, input)
     }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Runs foo.nu in the current context",
+                example: r#"source foo.nu"#,
+                result: None,
+            },
+            Example {
+                description: "Runs foo.nu in current context and call the command defined, suppose foo.nu has content: `def say-hi [] { echo 'Hi!' }`",
+                example: r#"source ./foo.nu; say-hi"#,
+                result: None,
+            },
+            Example {
+                description: "Runs foo.nu in current context and call the `main` command automatically, suppose foo.nu has content: `def main [] { echo 'Hi!' }`",
+                example: r#"source ./foo.nu"#,
+                result: None,
+            },
+        ]
+    }
 }

crates/nu-command/src/filesystem/save.rs

@@ -1,7 +1,9 @@
 use nu_engine::CallExt;
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Category, PipelineData, ShellError, Signature, Spanned, SyntaxShape, Value};
+use nu_protocol::{
+    Category, Example, PipelineData, ShellError, Signature, Spanned, SyntaxShape, Value,
+};
 use std::io::Write;
 
 use std::path::Path;
@@ -21,7 +23,7 @@ impl Command for Save {
     fn signature(&self) -> nu_protocol::Signature {
         Signature::build("save")
             .required("filename", SyntaxShape::Filepath, "the filename to use")
-            .switch("raw", "open file as raw binary", Some('r'))
+            .switch("raw", "save file as raw binary", Some('r'))
             .category(Category::FileSystem)
     }
 
@@ -115,4 +117,19 @@ impl Command for Save {
             }
         }
     }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Save a string to foo.txt in current directory",
+                example: r#"echo 'save me' | save foo.txt"#,
+                result: None,
+            },
+            Example {
+                description: "Save a record to foo.json in current directory",
+                example: r#"echo { a: 1, b: 2 } | save foo.json"#,
+                result: None,
+            },
+        ]
+    }
 }

crates/nu-command/src/filters/shuffle.rs

@@ -1,6 +1,8 @@
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Category, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature};
+use nu_protocol::{
+    Category, Example, IntoInterruptiblePipelineData, PipelineData, ShellError, Signature,
+};
 use rand::prelude::SliceRandom;
 use rand::thread_rng;
 
@@ -32,4 +34,13 @@ impl Command for Shuffle {
         let iter = v.into_iter();
         Ok(iter.into_pipeline_data(engine_state.ctrlc.clone()))
     }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description:
+                "Shuffle rows randomly(execute it a few more times and see the difference)",
+            example: r#"echo [[version patch]; [1.0.0 $false] [3.0.1 $true] [2.0.0 $false]] | shuffle"#,
+            result: None,
+        }]
+    }
 }

crates/nu-command/src/formats/from/tsv.rs

@@ -2,7 +2,7 @@ use super::delimited::from_delimited_data;
 
 use nu_protocol::ast::Call;
 use nu_protocol::engine::{Command, EngineState, Stack};
-use nu_protocol::{Category, Config, PipelineData, ShellError, Signature};
+use nu_protocol::{Category, Config, Example, PipelineData, ShellError, Signature};
 
 #[derive(Clone)]
 pub struct FromTsv;
@@ -36,6 +36,21 @@ impl Command for FromTsv {
         let config = stack.get_config().unwrap_or_default();
         from_tsv(call, input, &config)
     }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![
+            Example {
+                description: "Create a tsv file with header columns and open it",
+                example: r#"echo $'c1(char tab)c2(char tab)c3(char nl)1(char tab)2(char tab)3' | save tsv-data | open tsv-data | from tsv"#,
+                result: None,
+            },
+            Example {
+                description: "Create a tsv file without header columns and open it",
+                example: r#"echo $'a1(char tab)b1(char tab)c1(char nl)a2(char tab)b2(char tab)c2' | save tsv-data | open tsv-data | from tsv -n"#,
+                result: None,
+            },
+        ]
+    }
 }
 
 fn from_tsv(call: &Call, input: PipelineData, config: &Config) -> Result<PipelineData, ShellError> {