Merge pull request #1003 from andrasio/compact

Compact.

src/cli.rs

@@ -309,6 +309,7 @@ pub async fn cli() -> Result<(), Box<dyn Error>> {
             per_item_command(Where),
             per_item_command(Echo),
             whole_stream_command(Config),
+            whole_stream_command(Compact),
             whole_stream_command(SkipWhile),
             per_item_command(Enter),
             per_item_command(Help),

src/commands.rs

@@ -11,6 +11,7 @@ pub(crate) mod cd;
 pub(crate) mod classified;
 pub(crate) mod clip;
 pub(crate) mod command;
+pub(crate) mod compact;
 pub(crate) mod config;
 pub(crate) mod count;
 pub(crate) mod cp;
@@ -98,6 +99,7 @@ pub(crate) use command::{
 
 pub(crate) use append::Append;
 pub(crate) use classified::ClassifiedCommand;
+pub(crate) use compact::Compact;
 pub(crate) use config::Config;
 pub(crate) use count::Count;
 pub(crate) use cp::Cpy;

src/commands/compact.rs

@@ -0,0 +1,53 @@
+use crate::commands::WholeStreamCommand;
+use crate::errors::ShellError;
+use crate::parser::registry::{CommandRegistry, Signature};
+use crate::prelude::*;
+use futures::stream::StreamExt;
+
+pub struct Compact;
+
+#[derive(Deserialize)]
+pub struct CompactArgs {
+    rest: Vec<Tagged<String>>,
+}
+
+impl WholeStreamCommand for Compact {
+    fn name(&self) -> &str {
+        "compact"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("compact").rest(SyntaxShape::Any, "the columns to compact from the table")
+    }
+
+    fn usage(&self) -> &str {
+        "Creates a table with non-empty rows"
+    }
+
+    fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        args.process(registry, compact)?.run()
+    }
+}
+
+pub fn compact(
+    CompactArgs { rest: columns }: CompactArgs,
+    RunnableContext { input, .. }: RunnableContext,
+) -> Result<OutputStream, ShellError> {
+    let objects = input.values.take_while(move |item| {
+        let keep = if columns.is_empty() {
+            item.is_some()
+        } else {
+            columns
+                .iter()
+                .all(|field| item.get_data(field).borrow().is_some())
+        };
+
+        futures::future::ready(keep)
+    });
+
+    Ok(objects.from_input_stream())
+}

src/data/base.rs

@@ -498,6 +498,17 @@ impl Value {
         }
     }
 
+    pub(crate) fn is_some(&self) -> bool {
+        !self.is_none()
+    }
+
+    pub(crate) fn is_none(&self) -> bool {
+        match self {
+            Value::Primitive(Primitive::Nothing) => true,
+            _ => false,
+        }
+    }
+
     pub(crate) fn is_error(&self) -> bool {
         match self {
             Value::Error(_err) => true,