Bar Chart baseline. (#2621)

Bar Chart ready.

Cargo.lock

@@ -607,6 +607,12 @@ dependencies = [
  "zip",
 ]
 
+[[package]]
+name = "cassowary"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "df8670b8c7b9dae1793364eafadf7239c40d669904660c5960d74cfd80b46a53"
+
 [[package]]
 name = "cc"
 version = "1.0.59"
@@ -940,6 +946,22 @@ dependencies = [
  "winapi 0.3.9",
 ]
 
+[[package]]
+name = "crossterm"
+version = "0.18.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c2fcdc3c9cf8ee446222e8ee8691a6d21b563b8fe1a64b1873080db7b5b23cf0"
+dependencies = [
+ "bitflags",
+ "crossterm_winapi",
+ "lazy_static 1.4.0",
+ "libc",
+ "mio 0.7.0",
+ "parking_lot 0.11.0",
+ "signal-hook",
+ "winapi 0.3.9",
+]
+
 [[package]]
 name = "crossterm_winapi"
 version = "0.6.1"
@@ -2850,6 +2872,7 @@ dependencies = [
  "nu-test-support",
  "nu-value-ext",
  "nu_plugin_binaryview",
+ "nu_plugin_chart",
  "nu_plugin_fetch",
  "nu_plugin_from_bson",
  "nu_plugin_from_sqlite",
@@ -3116,7 +3139,7 @@ name = "nu_plugin_binaryview"
 version = "0.20.0"
 dependencies = [
  "ansi_term 0.12.1",
- "crossterm",
+ "crossterm 0.18.0",
  "image",
  "neso",
  "nu-errors",
@@ -3127,6 +3150,21 @@ dependencies = [
  "rawkey",
 ]
 
+[[package]]
+name = "nu_plugin_chart"
+version = "0.20.0"
+dependencies = [
+ "crossterm 0.18.0",
+ "nu-cli",
+ "nu-data",
+ "nu-errors",
+ "nu-plugin",
+ "nu-protocol",
+ "nu-source",
+ "nu-value-ext",
+ "tui",
+]
+
 [[package]]
 name = "nu_plugin_fetch"
 version = "0.20.0"
@@ -5471,6 +5509,19 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "tui"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c2eaeee894a1e9b90f80aa466fe59154fdb471980b5e104d8836fcea309ae17e"
+dependencies = [
+ "bitflags",
+ "cassowary",
+ "crossterm 0.17.8",
+ "unicode-segmentation",
+ "unicode-width",
+]
+
 [[package]]
 name = "typed-arena"
 version = "1.7.0"

Cargo.toml

@@ -27,6 +27,7 @@ nu-protocol = {version = "0.20.0", path = "./crates/nu-protocol"}
 nu-source = {version = "0.20.0", path = "./crates/nu-source"}
 nu-value-ext = {version = "0.20.0", path = "./crates/nu-value-ext"}
 
+nu_plugin_chart = {version = "0.20.0", path = "./crates/nu_plugin_chart", optional = true}
 nu_plugin_binaryview = {version = "0.20.0", path = "./crates/nu_plugin_binaryview", optional = true}
 nu_plugin_fetch = {version = "0.20.0", path = "./crates/nu_plugin_fetch", optional = true}
 nu_plugin_from_bson = {version = "0.20.0", path = "./crates/nu_plugin_from_bson", optional = true}
@@ -59,6 +60,16 @@ serde = {version = "1.0.115", features = ["derive"]}
 toml = "0.5.6"
 
 [features]
+ctrlc-support = ["nu-cli/ctrlc"]
+directories-support = ["nu-cli/directories", "nu-cli/dirs", "nu-data/directories", "nu-data/dirs"]
+git-support = ["nu-cli/git2"]
+ptree-support = ["nu-cli/ptree"]
+rich-benchmark = ["nu-cli/rich-benchmark"]
+rustyline-support = ["nu-cli/rustyline-support"]
+term-support = ["nu-cli/term"]
+uuid-support = ["nu-cli/uuid_crate"]
+which-support = ["nu-cli/ichwh", "nu-cli/which"]
+
 default = [
   "sys",
   "ps",
@@ -77,38 +88,30 @@ default = [
   "fetch",
   "rich-benchmark",
 ]
-extra = ["default", "binaryview", "tree", "clipboard-cli", "trash-support", "start", "bson", "sqlite", "s3"]
+extra = ["default", "binaryview", "tree", "clipboard-cli", "trash-support", "start", "bson", "sqlite", "s3", "chart"]
 stable = ["default"]
 
-# Default
+trace = ["nu-parser/trace"]
+
+# Stable (Default)
 inc = ["nu_plugin_inc"]
 ps = ["nu_plugin_ps"]
 sys = ["nu_plugin_sys"]
 textview = ["nu_plugin_textview"]
-
-# Stable
-binaryview = ["nu_plugin_binaryview"]
-bson = ["nu_plugin_from_bson", "nu_plugin_to_bson"]
 fetch = ["nu_plugin_fetch"]
 match = ["nu_plugin_match"]
 post = ["nu_plugin_post"]
+
+# Extra
+bson = ["nu_plugin_from_bson", "nu_plugin_to_bson"]
+chart = ["nu_plugin_chart"]
+binaryview = ["nu_plugin_binaryview"]
+clipboard-cli = ["nu-cli/clipboard-cli"]
+trash-support = ["nu-cli/trash-support"]
+start = ["nu_plugin_start"]
+tree = ["nu_plugin_tree"]
 s3 = ["nu_plugin_s3"]
 sqlite = ["nu_plugin_from_sqlite", "nu_plugin_to_sqlite"]
-start = ["nu_plugin_start"]
-trace = ["nu-parser/trace"]
-tree = ["nu_plugin_tree"]
-
-clipboard-cli = ["nu-cli/clipboard-cli"]
-ctrlc-support = ["nu-cli/ctrlc"]
-directories-support = ["nu-cli/directories", "nu-cli/dirs", "nu-data/directories", "nu-data/dirs"]
-git-support = ["nu-cli/git2"]
-ptree-support = ["nu-cli/ptree"]
-rich-benchmark = ["nu-cli/rich-benchmark"]
-rustyline-support = ["nu-cli/rustyline-support"]
-term-support = ["nu-cli/term"]
-trash-support = ["nu-cli/trash-support"]
-uuid-support = ["nu-cli/uuid_crate"]
-which-support = ["nu-cli/ichwh", "nu-cli/which"]
 
 # Core plugins that ship with `cargo install nu` by default
 # Currently, Cargo limits us to installing only one binary
@@ -170,6 +173,11 @@ name = "nu_plugin_extra_s3"
 path = "src/plugins/nu_plugin_extra_s3.rs"
 required-features = ["s3"]
 
+[[bin]]
+name = "nu_plugin_extra_chart"
+path = "src/plugins/nu_plugin_extra_chart.rs"
+required-features = ["chart"]
+
 # Main nu binary
 [[bin]]
 name = "nu"

crates/nu-cli/src/commands/histogram.rs

@@ -112,8 +112,9 @@ pub async fn histogram(
         nu_data::utils::Operation {
             grouper: Some(Box::new(move |_, _| Ok(String::from("frequencies")))),
             splitter: Some(splitter(column_grouper)),
-            format: None,
+            format: &None,
             eval: &evaluate_with,
+            reduction: &nu_data::utils::Reduction::Count,
         },
         &name,
     )?;
@@ -123,17 +124,33 @@ pub async fn histogram(
 
     Ok(futures::stream::iter(
         results
-            .percentages
+            .data
             .table_entries()
-            .map(move |value| {
+            .cloned()
-                let values = value.table_entries().cloned().collect::<Vec<_>>();
-                let occurrences = values.len();
-
-                (occurrences, values[occurrences - 1].clone())
-            })
             .collect::<Vec<_>>()
             .into_iter()
-            .map(move |(occurrences, value)| {
+            .zip(
+                results
+                    .percentages
+                    .table_entries()
+                    .cloned()
+                    .collect::<Vec<_>>()
+                    .into_iter(),
+            )
+            .map(move |(counts, percentages)| {
+                let percentage = percentages
+                    .table_entries()
+                    .cloned()
+                    .last()
+                    .unwrap_or_else(|| {
+                        UntaggedValue::decimal_from_float(0.0, name.span).into_value(&name)
+                    });
+                let value = counts
+                    .table_entries()
+                    .cloned()
+                    .last()
+                    .unwrap_or_else(|| UntaggedValue::int(0).into_value(&name));
+
                 let mut fact = TaggedDictBuilder::new(&name);
                 let column_value = labels
                     .get(idx)
@@ -147,19 +164,19 @@ pub async fn histogram(
                     .clone();
 
                 fact.insert_value(&column.item, column_value);
-                fact.insert_untagged("occurrences", UntaggedValue::int(occurrences));
+                fact.insert_untagged("count", value);
 
-                let percentage = format!(
+                let fmt_percentage = format!(
                     "{}%",
                     // Some(2) < the number of digits
                     // true < group the digits
-                    crate::commands::str_::from::action(&value, &name, Some(2), true)?
+                    crate::commands::str_::from::action(&percentage, &name, Some(2), true)?
                         .as_string()?
                 );
-                fact.insert_untagged("percentage", UntaggedValue::string(percentage));
+                fact.insert_untagged("percentage", UntaggedValue::string(fmt_percentage));
 
                 let string = std::iter::repeat("*")
-                    .take(value.as_u64().map_err(|_| {
+                    .take(percentage.as_u64().map_err(|_| {
                         ShellError::labeled_error("expected a number", "expected a number", &name)
                     })? as usize)
                     .collect::<String>();

crates/nu-cli/tests/commands/histogram.rs

@@ -54,7 +54,7 @@ fn summarizes_by_values() {
                 | get rusty_at
                 | histogram
                 | where value == "Estados Unidos"
-                | get occurrences
+                | get count
                 | echo $it
             "#
         ));
@@ -93,20 +93,19 @@ fn help() {
 }
 
 #[test]
-fn occurrences() {
+fn count() {
     let actual = nu!(
         cwd: ".", pipeline(
         r#"
-            echo "[{"bit":1},{"bit":0},{"bit":0},{"bit":0},{"bit":0},{"bit":0},{"bit":0},{"bit":1}]"
+            echo [[bit];  [1] [0] [0] [0] [0] [0] [0] [1]]
-            | from json
             | histogram bit
-            | sort-by occurrences
+            | sort-by count
             | reject frequency
             | to json
         "#
     ));
 
-    let bit_json = r#"[{"bit":"1","occurrences":2,"percentage":"33.33%"},{"bit":"0","occurrences":6,"percentage":"100.00%"}]"#;
+    let bit_json = r#"[{"bit":"1","count":2,"percentage":"33.33%"},{"bit":"0","count":6,"percentage":"100.00%"}]"#;
 
     assert_eq!(actual.out, bit_json);
 }

crates/nu-data/src/utils/internal.rs

@@ -1,6 +1,6 @@
 #![allow(clippy::type_complexity)]
 
-use crate::value::compute_values;
+use crate::value::unsafe_compute_values;
 use derive_new::new;
 use nu_errors::ShellError;
 use nu_protocol::hir::Operator;
@@ -23,6 +23,14 @@ impl Labels {
         }
     }
 
+    pub fn at_split(&self, idx: usize) -> Option<&str> {
+        if let Some(k) = self.y.get(idx) {
+            Some(&k[..])
+        } else {
+            None
+        }
+    }
+
     pub fn grouped(&self) -> impl Iterator<Item = &String> {
         self.x.iter()
     }
@@ -51,7 +59,7 @@ fn formula(
     calculator: Box<dyn Fn(Vec<&Value>) -> Result<Value, ShellError> + Send + Sync + 'static>,
 ) -> Box<dyn Fn(&Value, Vec<&Value>) -> Result<Value, ShellError> + Send + Sync + 'static> {
     Box::new(move |acc, datax| -> Result<Value, ShellError> {
-        let result = match compute_values(Operator::Multiply, &acc, &acc_begin) {
+        let result = match unsafe_compute_values(Operator::Multiply, &acc, &acc_begin) {
             Ok(v) => v.into_untagged_value(),
             Err((left_type, right_type)) => {
                 return Err(ShellError::coerce_error(
@@ -62,43 +70,100 @@ fn formula(
         };
 
         match calculator(datax) {
-            Ok(total) => Ok(match compute_values(Operator::Plus, &result, &total) {
+            Ok(total) => Ok(
-                Ok(v) => v.into_untagged_value(),
+                match unsafe_compute_values(Operator::Plus, &result, &total) {
-                Err((left_type, right_type)) => {
+                    Ok(v) => v.into_untagged_value(),
-                    return Err(ShellError::coerce_error(
+                    Err((left_type, right_type)) => {
-                        left_type.spanned_unknown(),
+                        return Err(ShellError::coerce_error(
-                        right_type.spanned_unknown(),
+                            left_type.spanned_unknown(),
-                    ))
+                            right_type.spanned_unknown(),
-                }
+                        ))
-            }),
+                    }
+                },
+            ),
             Err(reason) => Err(reason),
         }
     })
 }
 
 pub fn reducer_for(
-    command: Reduction,
+    command: &Reduction,
 ) -> Box<dyn Fn(&Value, Vec<&Value>) -> Result<Value, ShellError> + Send + Sync + 'static> {
     match command {
         Reduction::Accumulate => Box::new(formula(
             UntaggedValue::int(1).into_untagged_value(),
             Box::new(sum),
         )),
-        _ => Box::new(formula(
+        Reduction::Count => Box::new(formula(
             UntaggedValue::int(0).into_untagged_value(),
             Box::new(sum),
         )),
     }
 }
 
-pub fn max(values: &Value, tag: impl Into<Tag>) -> Result<&Value, ShellError> {
+pub fn max(values: &Value, tag: impl Into<Tag>) -> Result<Value, ShellError> {
     let tag = tag.into();
 
-    values
+    let mut x = UntaggedValue::int(0);
-        .table_entries()
+
-        .filter_map(|dataset| dataset.table_entries().max())
+    for split in values.table_entries() {
-        .max()
+        match split.value {
-        .ok_or_else(|| ShellError::labeled_error("err", "err", &tag))
+            UntaggedValue::Table(ref values) => {
+                let inner = inner_max(values)?;
+
+                if let Ok(greater_than) =
+                    crate::value::compare_values(Operator::GreaterThan, &inner.value, &x)
+                {
+                    if greater_than {
+                        x = inner.value.clone();
+                    }
+                } else {
+                    return Err(ShellError::unexpected(format!(
+                        "Could not compare\nleft: {:?}\nright: {:?}",
+                        inner.value, x
+                    )));
+                }
+            }
+            _ => {
+                return Err(ShellError::labeled_error(
+                    "Attempted to compute the sum of a value that cannot be summed.",
+                    "value appears here",
+                    split.tag.span,
+                ))
+            }
+        }
+    }
+
+    Ok(x.into_value(&tag))
+}
+
+pub fn inner_max(data: &[Value]) -> Result<Value, ShellError> {
+    let mut biggest = data
+        .first()
+        .ok_or_else(|| {
+            ShellError::unexpected("Cannot perform aggregate math operation on empty data")
+        })?
+        .value
+        .clone();
+
+    for value in data.iter() {
+        if let Ok(greater_than) =
+            crate::value::compare_values(Operator::GreaterThan, &value.value, &biggest)
+        {
+            if greater_than {
+                biggest = value.value.clone();
+            }
+        } else {
+            return Err(ShellError::unexpected(format!(
+                "Could not compare\nleft: {:?}\nright: {:?}",
+                biggest, value.value
+            )));
+        }
+    }
+    Ok(Value {
+        value: biggest,
+        tag: Tag::unknown(),
+    })
 }
 
 pub fn sum(data: Vec<&Value>) -> Result<Value, ShellError> {
@@ -107,7 +172,7 @@ pub fn sum(data: Vec<&Value>) -> Result<Value, ShellError> {
     for value in data {
         match value.value {
             UntaggedValue::Primitive(_) => {
-                acc = match compute_values(Operator::Plus, &acc, &value) {
+                acc = match unsafe_compute_values(Operator::Plus, &acc, &value) {
                     Ok(v) => v,
                     Err((left_type, right_type)) => {
                         return Err(ShellError::coerce_error(
@@ -133,19 +198,12 @@ pub fn sort_columns(
     values: &[String],
     format: &Option<Box<dyn Fn(&Value, String) -> Result<String, ShellError>>>,
 ) -> Result<Vec<String>, ShellError> {
-    let mut keys = vec![];
+    let mut keys = values.to_vec();
 
-    if let Some(fmt) = format {
+    if format.is_none() {
-        for k in values.iter() {
+        keys.sort();
-            let k = k.clone().tagged_unknown();
-            let v = crate::value::Date::naive_from_str(k.borrow_tagged())?.into_untagged_value();
-            keys.push(fmt(&v, k.to_string())?);
-        }
-    } else {
-        keys = values.to_vec();
     }
 
-    keys.sort();
     Ok(keys)
 }
 
@@ -167,17 +225,13 @@ pub fn sort(planes: &Labels, values: &Value, tag: impl Into<Tag>) -> Result<Valu
             let grouped = groups.get_data_by_key(key.borrow_spanned());
 
             if let Some(grouped) = grouped {
-                y.push(grouped.table_entries().cloned().collect::<Vec<_>>());
+                y.push(grouped);
             } else {
-                let empty = UntaggedValue::table(&[]).into_value(&tag);
+                y.push(UntaggedValue::Table(vec![]).into_value(&tag));
-                y.push(empty.table_entries().cloned().collect::<Vec<_>>());
             }
         }
 
-        x.push(
+        x.push(UntaggedValue::table(&y).into_value(&tag));
-            UntaggedValue::table(&y.iter().cloned().flatten().collect::<Vec<Value>>())
-                .into_value(&tag),
-        );
     }
 
     Ok(UntaggedValue::table(&x).into_value(&tag))
@@ -195,17 +249,27 @@ pub fn evaluate(
         let mut y = vec![];
 
         for (idx, subset) in split.table_entries().enumerate() {
-            let mut set = vec![];
+            if let UntaggedValue::Table(values) = &subset.value {
+                if let Some(ref evaluator) = evaluator {
+                    let mut evaluations = vec![];
 
-            if let Some(ref evaluator) = evaluator {
+                    for set in values.iter() {
-                let value = evaluator(idx, subset)?;
+                        evaluations.push(evaluator(idx, set)?);
+                    }
 
-                set.push(value);
+                    y.push(UntaggedValue::Table(evaluations).into_value(&tag));
-            } else {
+                } else {
-                set.push(UntaggedValue::int(1).into_value(&tag));
+                    y.push(
+                        UntaggedValue::Table(
+                            values
+                                .iter()
+                                .map(|_| UntaggedValue::int(1).into_value(&tag))
+                                .collect::<Vec<_>>(),
+                        )
+                        .into_value(&tag),
+                    );
+                }
             }
-
-            y.push(UntaggedValue::table(&set).into_value(&tag));
         }
 
         x.push(UntaggedValue::table(&y).into_value(&tag));
@@ -215,14 +279,17 @@ pub fn evaluate(
 }
 
 pub enum Reduction {
-    #[allow(dead_code)]
     Count,
     Accumulate,
 }
 
-pub fn reduce(values: &Value, tag: impl Into<Tag>) -> Result<Value, ShellError> {
+pub fn reduce(
+    values: &Value,
+    reduction_with: &Reduction,
+    tag: impl Into<Tag>,
+) -> Result<Value, ShellError> {
     let tag = tag.into();
-    let reduce_with = reducer_for(Reduction::Accumulate);
+    let reduce_with = reducer_for(reduction_with);
 
     let mut datasets = vec![];
     for dataset in values.table_entries() {
@@ -255,8 +322,8 @@ pub fn percentages(
                     .filter_map(|s| {
                         let hundred = UntaggedValue::decimal_from_float(100.0, tag.span);
 
-                        match compute_values(Operator::Divide, &hundred, &maxima) {
+                        match unsafe_compute_values(Operator::Divide, &hundred, &maxima) {
-                            Ok(v) => match compute_values(Operator::Multiply, &s, &v) {
+                            Ok(v) => match unsafe_compute_values(Operator::Multiply, &s, &v) {
                                 Ok(v) => Some(v.into_untagged_value()),
                                 Err(_) => None,
                             },

crates/nu-data/src/utils/mod.rs

@@ -6,6 +6,7 @@ mod internal;
 pub use crate::utils::group::group;
 pub use crate::utils::split::split;
 
+pub use crate::utils::internal::Reduction;
 use crate::utils::internal::*;
 
 use derive_new::new;
@@ -27,8 +28,9 @@ pub struct Model {
 pub struct Operation<'a> {
     pub grouper: Option<Box<dyn Fn(usize, &Value) -> Result<String, ShellError> + Send>>,
     pub splitter: Option<Box<dyn Fn(usize, &Value) -> Result<String, ShellError> + Send>>,
-    pub format: Option<Box<dyn Fn(&Value, String) -> Result<String, ShellError>>>,
+    pub format: &'a Option<Box<dyn Fn(&Value, String) -> Result<String, ShellError>>>,
     pub eval: &'a Option<Box<dyn Fn(usize, &Value) -> Result<Value, ShellError> + Send>>,
+    pub reduction: &'a Reduction,
 }
 
 pub fn report(
@@ -46,19 +48,17 @@ pub fn report(
         .map(|(key, _)| key.clone())
         .collect::<Vec<_>>();
 
-    let x = if options.format.is_some() {
+    let x = sort_columns(&x, &options.format)?;
-        sort_columns(&x, &options.format)
-    } else {
-        sort_columns(&x, &None)
-    }?;
 
     let mut y = splitted
         .row_entries()
         .map(|(key, _)| key.clone())
         .collect::<Vec<_>>();
+
     y.sort();
 
     let planes = Labels { x, y };
+
     let sorted = sort(&planes, &splitted, &tag)?;
 
     let evaluated = evaluate(
@@ -72,11 +72,11 @@ pub fn report(
     )?;
 
     let group_labels = planes.grouping_total();
+    let split_labels = planes.splits_total();
 
-    let reduced = reduce(&evaluated, &tag)?;
+    let reduced = reduce(&evaluated, options.reduction, &tag)?;
 
-    let max = max(&reduced, &tag)?.clone();
+    let maxima = max(&reduced, &tag)?;
-    let maxima = max.clone();
 
     let percents = percentages(&maxima, &reduced, &tag)?;
 
@@ -89,7 +89,7 @@ pub fn report(
             },
             Range {
                 start: UntaggedValue::int(0).into_untagged_value(),
-                end: max,
+                end: split_labels,
             },
         ),
         data: reduced,
@@ -99,7 +99,6 @@ pub fn report(
 
 pub mod helpers {
     use super::Model;
-    use bigdecimal::BigDecimal;
     use indexmap::indexmap;
     use nu_errors::ShellError;
     use nu_protocol::{UntaggedValue, Value};
@@ -113,10 +112,6 @@ pub mod helpers {
         UntaggedValue::int(s).into_untagged_value()
     }
 
-    pub fn decimal(f: impl Into<BigDecimal>) -> Value {
-        UntaggedValue::decimal(f.into()).into_untagged_value()
-    }
-
     pub fn decimal_from_float(f: f64, span: Span) -> Value {
         UntaggedValue::decimal_from_float(f, span).into_untagged_value()
     }
@@ -216,9 +211,12 @@ pub mod helpers {
     }
 
     pub fn date_formatter(
-        fmt: &'static str,
+        fmt: String,
     ) -> Box<dyn Fn(&Value, String) -> Result<String, ShellError>> {
-        Box::new(move |date: &Value, _: String| date.format(&fmt))
+        Box::new(move |date: &Value, _: String| {
+            let fmt = fmt.clone();
+            date.format(&fmt)
+        })
     }
 
     pub fn assert_without_checking_percentages(report_a: Model, report_b: Model) {
@@ -232,23 +230,24 @@ pub mod helpers {
 #[cfg(test)]
 mod tests {
     use super::helpers::{
-        assert_without_checking_percentages, committers, date_formatter, decimal,
+        assert_without_checking_percentages, committers, date_formatter, decimal_from_float, int,
-        decimal_from_float, int, table,
+        table,
     };
-    use super::{report, Labels, Model, Operation, Range};
+    use super::{report, Labels, Model, Operation, Range, Reduction};
     use nu_errors::ShellError;
     use nu_protocol::Value;
     use nu_source::{Span, Tag, TaggedItem};
     use nu_value_ext::ValueExt;
+
     #[test]
-    fn prepares_report_using_accumulating_value() {
+    fn prepares_report_using_counting_value() {
         let committers = table(&committers());
 
         let by_date = Box::new(move |_, row: &Value| {
             let key = String::from("date").tagged_unknown();
             let key = row.get_data_by_key(key.borrow_spanned()).unwrap();
 
-            let callback = date_formatter("%Y-%m-%d");
+            let callback = date_formatter("%Y-%m-%d".to_string());
             callback(&key, "nothing".to_string())
         });
 
@@ -261,7 +260,7 @@ mod tests {
         let options = Operation {
             grouper: Some(by_date),
             splitter: Some(by_country),
-            format: Some(date_formatter("%Y-%m-%d")),
+            format: &None,
             eval: /* value to be used for accumulation */ &Some(Box::new(move |_, value: &Value| {
                 let chickens_key = String::from("chickens").tagged_unknown();
 
@@ -275,6 +274,7 @@ mod tests {
                         )
                     })
             })),
+            reduction: &Reduction::Count
         };
 
         assert_without_checking_percentages(
@@ -295,29 +295,29 @@ mod tests {
                     },
                     Range {
                         start: int(0),
-                        end: int(60),
+                        end: int(3),
                     },
                 ),
                 data: table(&[
-                    table(&[int(10), int(30), int(60)]),
+                    table(&[int(10), int(20), int(30)]),
-                    table(&[int(5), int(15), int(30)]),
+                    table(&[int(5), int(10), int(15)]),
-                    table(&[int(2), int(6), int(12)]),
+                    table(&[int(2), int(4), int(6)]),
                 ]),
                 percentages: table(&[
+                    table(&[
+                        decimal_from_float(33.33, Span::unknown()),
+                        decimal_from_float(66.66, Span::unknown()),
+                        decimal_from_float(99.99, Span::unknown()),
+                    ]),
                     table(&[
                         decimal_from_float(16.66, Span::unknown()),
-                        decimal(50),
+                        decimal_from_float(33.33, Span::unknown()),
-                        decimal(100),
+                        decimal_from_float(49.99, Span::unknown()),
                     ]),
                     table(&[
-                        decimal_from_float(8.33, Span::unknown()),
+                        decimal_from_float(6.66, Span::unknown()),
-                        decimal(25),
+                        decimal_from_float(13.33, Span::unknown()),
-                        decimal(50),
+                        decimal_from_float(19.99, Span::unknown()),
-                    ]),
-                    table(&[
-                        decimal_from_float(3.33, Span::unknown()),
-                        decimal(10),
-                        decimal(20),
                     ]),
                 ]),
             },

crates/nu-data/src/utils/split.rs

@@ -16,7 +16,7 @@ pub fn split(
     let mut out = TaggedDictBuilder::new(&tag);
 
     if splitter.is_none() {
-        out.insert_untagged("table", UntaggedValue::table(&[value.clone()]));
+        out.insert_untagged("table", value.clone());
         return Ok(out.into_value());
     }
 

crates/nu-protocol/src/value/iter.rs

@@ -1,10 +1,12 @@
 use crate::value::{UntaggedValue, Value};
 
+#[derive(Debug)]
 pub enum RowValueIter<'a> {
     Empty,
     Entries(indexmap::map::Iter<'a, String, Value>),
 }
 
+#[derive(Debug)]
 pub enum TableValueIter<'a> {
     Empty,
     Entries(std::slice::Iter<'a, Value>),

crates/nu_plugin_binaryview/Cargo.toml

@@ -11,7 +11,7 @@ doctest = false
 
 [dependencies]
 ansi_term = "0.12.1"
-crossterm = "0.17"
+crossterm = "0.18"
 image = {version = "0.22.4", default_features = false, features = ["png_codec", "jpeg"]}
 neso = "0.5.0"
 nu-errors = {path = "../nu-errors", version = "0.20.0"}

crates/nu_plugin_chart/Cargo.toml

@@ -0,0 +1,22 @@
+[package]
+authors = ["The Nu Project Contributors"]
+description = "A plugin to display charts"
+edition = "2018"
+license = "MIT"
+name = "nu_plugin_chart"
+version = "0.20.0"
+
+[lib]
+doctest = false
+
+[dependencies]
+nu-data = {path = "../nu-data", version = "0.20.0"}
+nu-errors = {path = "../nu-errors", version = "0.20.0"}
+nu-plugin = {path = "../nu-plugin", version = "0.20.0"}
+nu-protocol = {path = "../nu-protocol", version = "0.20.0"}
+nu-source = {path = "../nu-source", version = "0.20.0"}
+nu-cli = {path = "../nu-cli", version = "0.20.0"}
+nu-value-ext = {path = "../nu-value-ext", version = "0.20.0"}
+
+crossterm = "0.18"
+tui = {version = "0.12.0", default-features = false, features = ["crossterm"]}

crates/nu_plugin_chart/src/chart.rs

@@ -0,0 +1,155 @@
+use nu_errors::ShellError;
+use nu_protocol::Value;
+use nu_source::Tagged;
+
+use tui::{
+    layout::{Constraint, Direction, Layout},
+    style::{Color, Modifier, Style},
+    widgets::{BarChart as TuiBarChart, Block, Borders},
+};
+
+pub enum Columns {
+    One(Tagged<String>),
+    Two(Tagged<String>, Tagged<String>),
+    None,
+}
+
+#[allow(clippy::type_complexity)]
+pub struct Chart {
+    pub reduction: nu_data::utils::Reduction,
+    pub columns: Columns,
+    pub eval: Option<Box<dyn Fn(usize, &Value) -> Result<Value, ShellError> + Send>>,
+    pub format: Option<String>,
+}
+
+impl Default for Chart {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+impl Chart {
+    pub fn new() -> Chart {
+        Chart {
+            reduction: nu_data::utils::Reduction::Count,
+            columns: Columns::None,
+            eval: None,
+            format: None,
+        }
+    }
+}
+
+pub struct BarChart<'a> {
+    pub title: &'a str,
+    pub data: Vec<(&'a str, u64)>,
+    pub enhanced_graphics: bool,
+}
+
+impl<'a> BarChart<'a> {
+    pub fn from_model(model: &'a nu_data::utils::Model) -> Result<BarChart<'a>, ShellError> {
+        let mut data = Vec::new();
+        let mut data_points = Vec::new();
+
+        for percentages in model
+            .percentages
+            .table_entries()
+            .cloned()
+            .collect::<Vec<_>>()
+            .into_iter()
+        {
+            let mut percentages_collected = vec![];
+
+            for percentage in percentages
+                .table_entries()
+                .cloned()
+                .collect::<Vec<_>>()
+                .into_iter()
+            {
+                percentages_collected.push(percentage.as_u64()?);
+            }
+
+            data_points.push(percentages_collected);
+        }
+
+        let mark_in = if model.labels.y.len() <= 1 {
+            0
+        } else {
+            (model.labels.y.len() as f64 / 2.0).floor() as usize
+        };
+
+        for idx in 0..model.labels.x.len() {
+            let mut current = 0;
+
+            loop {
+                let label = if current == mark_in {
+                    model
+                        .labels
+                        .at(idx)
+                        .ok_or_else(|| ShellError::untagged_runtime_error("Could not load data"))?
+                } else {
+                    ""
+                };
+
+                let percentages_collected = data_points
+                    .get(current)
+                    .ok_or_else(|| ShellError::untagged_runtime_error("Could not load data"))?;
+
+                data.push((
+                    label,
+                    *percentages_collected
+                        .get(idx)
+                        .ok_or_else(|| ShellError::untagged_runtime_error("Could not load data"))?,
+                ));
+
+                current += 1;
+
+                if current == model.labels.y.len() {
+                    break;
+                }
+            }
+        }
+
+        Ok(BarChart {
+            title: "Bar Chart",
+            data: (&data[..]).to_vec(),
+            enhanced_graphics: true,
+        })
+    }
+
+    pub fn draw<T>(&mut self, ui: &mut tui::Terminal<T>) -> std::io::Result<()>
+    where
+        T: tui::backend::Backend,
+    {
+        ui.draw(|f| {
+            let chunks = Layout::default()
+                .direction(Direction::Vertical)
+                .margin(2)
+                .constraints([Constraint::Percentage(100)].as_ref())
+                .split(f.size());
+
+            let barchart = TuiBarChart::default()
+                .block(Block::default().title("Chart").borders(Borders::ALL))
+                .data(&self.data)
+                .bar_width(9)
+                .bar_style(Style::default().fg(Color::Green))
+                .value_style(
+                    Style::default()
+                        .bg(Color::Green)
+                        .add_modifier(Modifier::BOLD),
+                );
+
+            f.render_widget(barchart, chunks[0]);
+        })
+    }
+
+    pub fn on_right(&mut self) {
+        let one_bar = self.data.remove(0);
+        self.data.push(one_bar);
+    }
+
+    pub fn on_left(&mut self) {
+        if let Some(one_bar) = self.data.pop() {
+            self.data.insert(0, one_bar);
+        }
+    }
+}

crates/nu_plugin_chart/src/lib.rs

@@ -0,0 +1,4 @@
+mod chart;
+mod nu;
+
+pub use chart::Chart;

crates/nu_plugin_chart/src/main.rs

@@ -0,0 +1,6 @@
+use nu_plugin::serve_plugin;
+use nu_plugin_chart::Chart;
+
+fn main() {
+    serve_plugin(&mut Chart::new());
+}

crates/nu_plugin_chart/src/nu/mod.rs

@@ -0,0 +1,330 @@
+use nu_errors::ShellError;
+use nu_plugin::Plugin;
+use nu_protocol::{CallInfo, ColumnPath, Primitive, Signature, SyntaxShape, UntaggedValue, Value};
+use nu_source::TaggedItem;
+use nu_value_ext::ValueExt;
+
+use crate::chart::{BarChart, Chart, Columns};
+
+use std::{
+    error::Error,
+    io::{stdout, Write},
+    sync::mpsc,
+    thread,
+    time::{Duration, Instant},
+};
+
+use crossterm::{
+    event::{self, DisableMouseCapture, EnableMouseCapture, Event as CEvent, KeyCode},
+    execute,
+    terminal::{disable_raw_mode, enable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
+};
+
+use tui::{backend::CrosstermBackend, Terminal};
+
+enum Event<I> {
+    Input(I),
+    Tick,
+}
+
+fn display(model: &nu_data::utils::Model) -> Result<(), Box<dyn Error>> {
+    let mut app = BarChart::from_model(&model)?;
+
+    enable_raw_mode()?;
+
+    let mut stdout = stdout();
+    execute!(stdout, EnterAlternateScreen, EnableMouseCapture)?;
+
+    let backend = CrosstermBackend::new(stdout);
+
+    let mut terminal = Terminal::new(backend)?;
+
+    let (tx, rx) = mpsc::channel();
+
+    let tick_rate = Duration::from_millis(250);
+    thread::spawn(move || {
+        let mut last_tick = Instant::now();
+        loop {
+            if event::poll(tick_rate - last_tick.elapsed()).is_ok() {
+                if let Ok(CEvent::Key(key)) = event::read() {
+                    let _ = tx.send(Event::Input(key));
+                }
+            }
+            if last_tick.elapsed() >= tick_rate {
+                let _ = tx.send(Event::Tick);
+                last_tick = Instant::now();
+            }
+        }
+    });
+
+    terminal.clear()?;
+
+    loop {
+        app.draw(&mut terminal)?;
+
+        match rx.recv()? {
+            Event::Input(event) => match event.code {
+                KeyCode::Char('q') => {
+                    disable_raw_mode()?;
+                    execute!(
+                        terminal.backend_mut(),
+                        LeaveAlternateScreen,
+                        DisableMouseCapture
+                    )?;
+                    terminal.show_cursor()?;
+                    break;
+                }
+                KeyCode::Left => app.on_left(),
+                KeyCode::Right => app.on_right(),
+                _ => {}
+            },
+            Event::Tick => {}
+        }
+    }
+
+    Ok(())
+}
+
+impl Plugin for Chart {
+    fn config(&mut self) -> Result<Signature, ShellError> {
+        Ok(Signature::build("chart")
+            .desc("Displays bar charts")
+            .switch("acc", "accumuate values", Some('a'))
+            .optional(
+                "columns",
+                SyntaxShape::Any,
+                "the columns to chart [x-axis y-axis]",
+            )
+            .named(
+                "use",
+                SyntaxShape::ColumnPath,
+                "column to use for evaluation",
+                Some('u'),
+            )
+            .named(
+                "format",
+                SyntaxShape::String,
+                "Specify date and time formatting",
+                Some('f'),
+            ))
+    }
+
+    fn sink(&mut self, call_info: CallInfo, input: Vec<Value>) {
+        if let Some(Value {
+            value: UntaggedValue::Primitive(Primitive::Boolean(true)),
+            ..
+        }) = call_info.args.get("acc")
+        {
+            self.reduction = nu_data::utils::Reduction::Accumulate;
+        }
+
+        let _ = self.run(call_info, input);
+    }
+}
+
+impl Chart {
+    fn run(&mut self, call_info: CallInfo, input: Vec<Value>) -> Result<(), ShellError> {
+        let args = call_info.args;
+        let name = call_info.name_tag;
+
+        self.eval = if let Some(path) = args.get("use") {
+            Some(evaluator(path.as_column_path()?.item))
+        } else {
+            None
+        };
+
+        self.format = if let Some(fmt) = args.get("format") {
+            Some(fmt.as_string()?)
+        } else {
+            None
+        };
+
+        for arg in args.positional_iter() {
+            match arg {
+                Value {
+                    value: UntaggedValue::Primitive(Primitive::String(column)),
+                    tag,
+                } => {
+                    let column = column.clone();
+                    self.columns = Columns::One(column.tagged(tag));
+                }
+                Value {
+                    value: UntaggedValue::Table(arguments),
+                    tag,
+                } => {
+                    if arguments.len() > 1 {
+                        let col1 = arguments
+                            .get(0)
+                            .ok_or_else(|| {
+                                ShellError::labeled_error(
+                                    "expected file and replace strings eg) [find replace]",
+                                    "missing find-replace values",
+                                    tag,
+                                )
+                            })?
+                            .as_string()?
+                            .tagged(tag);
+
+                        let col2 = arguments
+                            .get(1)
+                            .ok_or_else(|| {
+                                ShellError::labeled_error(
+                                    "expected file and replace strings eg) [find replace]",
+                                    "missing find-replace values",
+                                    tag,
+                                )
+                            })?
+                            .as_string()?
+                            .tagged(tag);
+
+                        self.columns = Columns::Two(col1, col2);
+                    } else {
+                        let col1 = arguments
+                            .get(0)
+                            .ok_or_else(|| {
+                                ShellError::labeled_error(
+                                    "expected file and replace strings eg) [find replace]",
+                                    "missing find-replace values",
+                                    tag,
+                                )
+                            })?
+                            .as_string()?
+                            .tagged(tag);
+
+                        self.columns = Columns::One(col1);
+                    }
+                }
+                _ => {}
+            }
+        }
+
+        let data = UntaggedValue::table(&input).into_value(&name);
+
+        match &self.columns {
+            Columns::Two(col1, col2) => {
+                let key = col1.clone();
+                let fmt = self.format.clone();
+
+                let grouper = Box::new(move |_: usize, row: &Value| {
+                    let key = key.clone();
+                    let fmt = fmt.clone();
+
+                    match row.get_data_by_key(key.borrow_spanned()) {
+                        Some(key) => {
+                            if let Some(fmt) = fmt {
+                                let callback = nu_data::utils::helpers::date_formatter(fmt);
+                                callback(&key, "nothing".to_string())
+                            } else {
+                                nu_value_ext::as_string(&key)
+                            }
+                        }
+                        None => Err(ShellError::labeled_error(
+                            "unknown column",
+                            "unknown column",
+                            key.tag(),
+                        )),
+                    }
+                });
+
+                let key = col2.clone();
+                let splitter = Box::new(move |_: usize, row: &Value| {
+                    let key = key.clone();
+
+                    match row.get_data_by_key(key.borrow_spanned()) {
+                        Some(key) => nu_value_ext::as_string(&key),
+                        None => Err(ShellError::labeled_error(
+                            "unknown column",
+                            "unknown column",
+                            key.tag(),
+                        )),
+                    }
+                });
+
+                let formatter = if self.format.is_some() {
+                    let default = String::from("%b-%Y");
+
+                    let string_fmt = self.format.as_ref().unwrap_or_else(|| &default);
+
+                    Some(nu_data::utils::helpers::date_formatter(
+                        string_fmt.to_string(),
+                    ))
+                } else {
+                    None
+                };
+
+                let options = nu_data::utils::Operation {
+                    grouper: Some(grouper),
+                    splitter: Some(splitter),
+                    format: &formatter,
+                    eval: &self.eval,
+                    reduction: &self.reduction,
+                };
+
+                let _ = display(&nu_data::utils::report(&data, options, &name)?);
+            }
+            Columns::One(col) => {
+                let key = col.clone();
+                let fmt = self.format.clone();
+
+                let grouper = Box::new(move |_: usize, row: &Value| {
+                    let key = key.clone();
+                    let fmt = fmt.clone();
+
+                    match row.get_data_by_key(key.borrow_spanned()) {
+                        Some(key) => {
+                            if let Some(fmt) = fmt {
+                                let callback = nu_data::utils::helpers::date_formatter(fmt);
+                                callback(&key, "nothing".to_string())
+                            } else {
+                                nu_value_ext::as_string(&key)
+                            }
+                        }
+                        None => Err(ShellError::labeled_error(
+                            "unknown column",
+                            "unknown column",
+                            key.tag(),
+                        )),
+                    }
+                });
+
+                let formatter = if self.format.is_some() {
+                    let default = String::from("%b-%Y");
+
+                    let string_fmt = self.format.as_ref().unwrap_or_else(|| &default);
+
+                    Some(nu_data::utils::helpers::date_formatter(
+                        string_fmt.to_string(),
+                    ))
+                } else {
+                    None
+                };
+
+                let options = nu_data::utils::Operation {
+                    grouper: Some(grouper),
+                    splitter: None,
+                    format: &formatter,
+                    eval: &self.eval,
+                    reduction: &self.reduction,
+                };
+
+                let _ = display(&nu_data::utils::report(&data, options, &name)?);
+            }
+            _ => {}
+        }
+
+        Ok(())
+    }
+}
+
+pub fn evaluator(by: ColumnPath) -> Box<dyn Fn(usize, &Value) -> Result<Value, ShellError> + Send> {
+    Box::new(move |_: usize, value: &Value| {
+        let path = by.clone();
+
+        let eval = nu_value_ext::get_data_by_column_path(value, &path, move |_, _, error| error);
+
+        match eval {
+            Ok(with_value) => Ok(with_value),
+            Err(reason) => Err(reason),
+        }
+    })
+}

docs/commands/histogram.md

@@ -35,7 +35,7 @@ If we now want to see how often the different numbers were generated, we can use
 ```shell
 > open random_numbers.csv | histogram "random numbers"
 ───┬────────────────┬─────────────┬────────────┬──────────────────────────────────────────────────────────────────────────────────────────────────────
- # │ random numbers │ occurrences │ percentage │ frequency
+ # │ random numbers │    count    │ percentage │ frequency
 ───┼────────────────┼─────────────┼────────────┼──────────────────────────────────────────────────────────────────────────────────────────────────────
  0 │ 0              │           8 │ 57.14%     │ *********************************************************
  1 │ 1              │          14 │ 100.00%    │ ****************************************************************************************************
@@ -51,7 +51,7 @@ We can also set the name of the second column or sort the table:
 ```shell
 > open random_numbers.csv | histogram "random numbers" probability
 ───┬────────────────┬─────────────┬────────────┬──────────────────────────────────────────────────────────────────────────────────────────────────────
- # │ random numbers │ occurrences │ percentage │ probability
+ # │ random numbers │    count    │ percentage │ probability
 ───┼────────────────┼─────────────┼────────────┼──────────────────────────────────────────────────────────────────────────────────────────────────────
  0 │ 0              │           8 │ 57.14%     │ *********************************************************
  1 │ 1              │          14 │ 100.00%    │ ****************************************************************************************************
@@ -66,7 +66,7 @@ We can also set the name of the second column or sort the table:
 ```shell
 > open random_numbers.csv | histogram "random numbers" probability | sort-by probability
 ───┬────────────────┬─────────────┬────────────┬──────────────────────────────────────────────────────────────────────────────────────────────────────
- # │ random numbers │ occurrences │ percentage │ probability
+ # │ random numbers │    count    │ percentage │ probability
 ───┼────────────────┼─────────────┼────────────┼──────────────────────────────────────────────────────────────────────────────────────────────────────
  0 │ 4              │           3 │ 21.43%     │ *********************
  1 │ 3              │           6 │ 42.86%     │ ******************************************
@@ -81,9 +81,9 @@ We can also set the name of the second column or sort the table:
 Of course, histogram operations are not restricted to just analyzing numbers in files, you can also analyze your directories
 
 ```shell
-> ls -la | histogram type | sort-by occurrences
+> ls -la | histogram type | sort-by count
 ───┬─────────┬─────────────┬────────────┬──────────────────────────────────────────────────────────────────────────────────────────────────────
- # │ type    │ occurrences │ percentage │ frequency
+ # │ type    │    count    │ percentage │ frequency
 ───┼─────────┼─────────────┼────────────┼──────────────────────────────────────────────────────────────────────────────────────────────────────
  0 │ Dir     │           5 │ 4.76%      │ ****
  1 │ Symlink │          28 │ 26.67%     │ **************************

src/plugins/nu_plugin_extra_chart.rs

@@ -0,0 +1,6 @@
+use nu_plugin::serve_plugin;
+use nu_plugin_chart::Chart;
+
+fn main() {
+    serve_plugin(&mut Chart::new());
+}