Added math product support (#2249)

* added math product: working initial impl

* resolving merge conflicts

* impl std::ops::Mul for Filesize

* rebased with main; refactored product implementation

* fixed error msg, added docs for math product

Cargo.lock

@@ -277,9 +277,9 @@ checksum = "1d49d90015b3c36167a20fe2810c5cd875ad504b39cff3d4eae7977e6b7c1cb2"
 
 [[package]]
 name = "autocfg"
-version = "1.0.0"
+version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f8aac770f1885fd7e387acedd76065302551364496e46b3dd00860b2f8359b9d"
+checksum = "cdb031dd78e28731d87d56cc8ffef4a8f36ca26c38fe2de700543e627f8a464a"
 
 [[package]]
 name = "backtrace"
@@ -896,6 +896,16 @@ dependencies = [
  "crossbeam-utils 0.6.6",
 ]
 
+[[package]]
+name = "crossbeam-channel"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "09ee0cc8804d5393478d743b035099520087a5186f3b93fa58cec08fa62407b6"
+dependencies = [
+ "cfg-if",
+ "crossbeam-utils 0.7.2",
+]
+
 [[package]]
 name = "crossbeam-deque"
 version = "0.7.3"
@@ -913,7 +923,7 @@ version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "058ed274caafc1f60c4997b5fc07bf7dc7cca454af7c6e81edffe5f33f70dace"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
  "cfg-if",
  "crossbeam-utils 0.7.2",
  "lazy_static 1.4.0",
@@ -949,7 +959,7 @@ version = "0.7.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c3c7c73a2d1e9fc0886a08b93e98eb643461230d5f1925e4036204d5f2e261a8"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
  "cfg-if",
  "lazy_static 1.4.0",
 ]
@@ -1343,9 +1353,9 @@ checksum = "a246d82be1c9d791c5dfde9a2bd045fc3cbba3fa2b11ad558f27d01712f00569"
 
 [[package]]
 name = "encoding_rs"
-version = "0.8.23"
+version = "0.8.24"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e8ac63f94732332f44fe654443c46f6375d1939684c17b0afb6cb56b0456e171"
+checksum = "a51b8cf747471cb9499b6d59e59b0444f4c90eba8968c4e44874e92b5b64ace2"
 dependencies = [
  "cfg-if",
 ]
@@ -1384,9 +1394,9 @@ dependencies = [
 
 [[package]]
 name = "event-listener"
-version = "2.3.3"
+version = "2.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7f14646a9e0430150a87951622ba9675472b68e384b7701b8423b30560805c7a"
+checksum = "e1cd41440ae7e4734bbd42302f63eaba892afc93a3912dad84006247f0dedb0e"
 
 [[package]]
 name = "failure"
@@ -1807,9 +1817,9 @@ checksum = "aaf91faf136cb47367fa430cd46e37a788775e7fa104f8b4bcb3861dc389b724"
 
 [[package]]
 name = "git2"
-version = "0.13.9"
+version = "0.13.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "83a18853c521bcf553a4e3c05ad21f3ad89c1a78a0485adc97829a4c88066a36"
+checksum = "86d97249f21e9542caeee9f8e1d150905cd875bf723f5ff771bdb4852eb83a24"
 dependencies = [
  "bitflags",
  "libc",
@@ -1863,7 +1873,7 @@ version = "0.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e91b62f79061a0bc2e046024cb7ba44b08419ed238ecbd9adbd787434b9e8c25"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
 ]
 
 [[package]]
@@ -2252,7 +2262,7 @@ version = "1.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "86b45e59b16c76b11bf9738fd5d38879d3bd28ad292d7b313608becb17ae2df9"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
  "hashbrown",
  "serde 1.0.115",
 ]
@@ -2310,7 +2320,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "17b77027f12e53ae59a379f7074259d32eb10867e6183388020e922832d9c3fb"
 dependencies = [
  "bytes 0.4.12",
- "crossbeam-channel",
+ "crossbeam-channel 0.3.9",
  "crossbeam-utils 0.6.6",
  "curl",
  "curl-sys",
@@ -2451,15 +2461,15 @@ checksum = "830d08ce1d1d941e6b30645f1a0eb5643013d835ce3779a5fc208261dbe10f55"
 
 [[package]]
 name = "libc"
-version = "0.2.74"
+version = "0.2.76"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a2f02823cf78b754822df5f7f268fb59822e7296276d3e069d8e8cb26a14bd10"
+checksum = "755456fae044e6fa1ebbbd1b3e902ae19e73097ed4ed87bb79934a867c007bc3"
 
 [[package]]
 name = "libgit2-sys"
-version = "0.12.11+1.0.1"
+version = "0.12.12+1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1f4755167bef8a2959fe4eedeece2ba0f8eb9923b209d46139031f1281d569a2"
+checksum = "0100ae90655025134424939f1f60e27e879460d451dff6afedde4f8226cbebfc"
 dependencies = [
  "cc",
  "libc",
@@ -2710,7 +2720,7 @@ version = "0.5.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c198b026e1bbf08a937e94c6c60f9ec4a2267f5b0d2eec9c1b21b061ce2be55f"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
 ]
 
 [[package]]
@@ -2741,9 +2751,9 @@ dependencies = [
 
 [[package]]
 name = "miniz_oxide"
-version = "0.4.0"
+version = "0.4.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "be0f75932c1f6cfae3c04000e40114adf955636e19040f9c0a2c380702aa1c7f"
+checksum = "4d7559a8a40d0f97e1edea3220f698f78b1c5ab67532e49f68fde3910323b722"
 dependencies = [
  "adler",
 ]
@@ -3478,7 +3488,7 @@ version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "090c7f9998ee0ff65aa5b723e4009f7b217707f1fb5ea551329cc4d6231fb304"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
  "num-integer",
  "num-traits 0.2.12",
  "serde 1.0.115",
@@ -3490,7 +3500,7 @@ version = "0.2.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b6b19411a9719e753aff12e5187b74d60d3dc449ec3f4dc21e3989c3f554bc95"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
  "num-traits 0.2.12",
 ]
 
@@ -3511,7 +3521,7 @@ version = "0.1.43"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8d59457e662d541ba17869cf51cf177c0b5f0cbf476c66bdc90bf1edac4f875b"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
  "num-traits 0.2.12",
 ]
 
@@ -3521,7 +3531,7 @@ version = "0.1.41"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7a6e6b7c748f995c4c29c5f5ae0248536e04a5739927c74ec0fa564805094b9f"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
  "num-integer",
  "num-traits 0.2.12",
 ]
@@ -3532,7 +3542,7 @@ version = "0.2.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5c000134b5dbf44adc5cb772486d335293351644b801551abe8f75c84cfa4aef"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
  "num-bigint",
  "num-integer",
  "num-traits 0.2.12",
@@ -3553,7 +3563,7 @@ version = "0.2.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ac267bcc07f48ee5f8935ab0d24f316fb722d7a1292e2913f0cc196b29ffd611"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
 ]
 
 [[package]]
@@ -3698,7 +3708,7 @@ version = "0.9.58"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a842db4709b604f0fe5d1170ae3565899be2ad3d9cbc72dedc789ac0511f78de"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
  "cc",
  "libc",
  "pkg-config",
@@ -4388,11 +4398,11 @@ dependencies = [
 
 [[package]]
 name = "rayon"
-version = "1.3.1"
+version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "62f02856753d04e03e26929f820d0a0a337ebe71f849801eea335d464b349080"
+checksum = "cfd016f0c045ad38b5251be2c9c0ab806917f82da4d36b2a327e5166adad9270"
 dependencies = [
- "autocfg 1.0.0",
+ "autocfg 1.0.1",
  "crossbeam-deque",
  "either",
  "rayon-core",
@@ -4400,12 +4410,12 @@ dependencies = [
 
 [[package]]
 name = "rayon-core"
-version = "1.7.1"
+version = "1.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e92e15d89083484e11353891f1af602cc661426deb9564c298b270c726973280"
+checksum = "91739a34c4355b5434ce54c9086c5895604a9c278586d1f1aa95e04f66b525a0"
 dependencies = [
+ "crossbeam-channel 0.4.3",
  "crossbeam-deque",
- "crossbeam-queue",
  "crossbeam-utils 0.7.2",
  "lazy_static 1.4.0",
  "num_cpus",
@@ -5187,9 +5197,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "1.0.38"
+version = "1.0.39"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e69abc24912995b3038597a7a593be5053eb0fb44f3cc5beec0deb421790c1f4"
+checksum = "891d8d6567fe7c7f8835a3a98af4208f3846fba258c1bc3c31d6e506239f11f9"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -5632,9 +5642,9 @@ dependencies = [
 
 [[package]]
 name = "trash"
-version = "1.1.0"
+version = "1.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bcd4ea126e9b491aa0ee8043f5519cd56498413997a6c3859c8a9812aa300803"
+checksum = "329be7bb48445d16bf4c241ba9514af46f2189c715bf5fd854e38f7c95f60194"
 dependencies = [
  "winapi 0.3.9",
 ]
@@ -5875,9 +5885,9 @@ checksum = "6454029bf181f092ad1b853286f23e2c507d8e8194d01d92da4a55c274a5508c"
 
 [[package]]
 name = "vec-arena"
-version = "0.5.0"
+version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "17dfb54bf57c9043f4616cb03dab30eff012cc26631b797d8354b916708db919"
+checksum = "8cb18268690309760d59ee1a9b21132c126ba384f374c59a94db4bc03adeb561"
 
 [[package]]
 name = "vec_map"

crates/nu-cli/src/cli.rs

@@ -419,6 +419,7 @@ pub fn create_default_context(
             whole_stream_command(MathStddev),
             whole_stream_command(MathSummation),
             whole_stream_command(MathVariance),
+            whole_stream_command(MathProduct),
             // File format output
             whole_stream_command(To),
             whole_stream_command(ToCSV),

crates/nu-cli/src/commands.rs

@@ -199,8 +199,8 @@ pub(crate) use last::Last;
 pub(crate) use lines::Lines;
 pub(crate) use ls::Ls;
 pub(crate) use math::{
-    Math, MathAverage, MathEval, MathMaximum, MathMedian, MathMinimum, MathMode, MathStddev,
+    Math, MathAverage, MathEval, MathMaximum, MathMedian, MathMinimum, MathMode, MathProduct,
-    MathSummation, MathVariance,
+    MathStddev, MathSummation, MathVariance,
 };
 pub(crate) use merge::Merge;
 pub(crate) use mkdir::Mkdir;

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

@@ -5,6 +5,7 @@ pub mod max;
 pub mod median;
 pub mod min;
 pub mod mode;
+pub mod product;
 pub mod stddev;
 pub mod sum;
 pub mod variance;
@@ -19,6 +20,7 @@ pub use max::SubCommand as MathMaximum;
 pub use median::SubCommand as MathMedian;
 pub use min::SubCommand as MathMinimum;
 pub use mode::SubCommand as MathMode;
+pub use product::SubCommand as MathProduct;
 pub use stddev::SubCommand as MathStddev;
 pub use sum::SubCommand as MathSummation;
 pub use variance::SubCommand as MathVariance;

crates/nu-cli/src/commands/math/product.rs

@@ -0,0 +1,126 @@
+use crate::commands::math::reducers::{reducer_for, Reduce};
+use crate::commands::math::utils::run_with_function;
+use crate::commands::WholeStreamCommand;
+use crate::prelude::*;
+use nu_errors::ShellError;
+use nu_protocol::{
+    hir::{convert_number_to_u64, Number},
+    Primitive, Signature, UntaggedValue, Value,
+};
+
+pub struct SubCommand;
+
+#[async_trait]
+impl WholeStreamCommand for SubCommand {
+    fn name(&self) -> &str {
+        "math product"
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build("math product")
+    }
+
+    fn usage(&self) -> &str {
+        "Finds the product of a list of numbers or tables"
+    }
+
+    async fn run(
+        &self,
+        args: CommandArgs,
+        registry: &CommandRegistry,
+    ) -> Result<OutputStream, ShellError> {
+        run_with_function(
+            RunnableContext {
+                input: args.input,
+                registry: registry.clone(),
+                shell_manager: args.shell_manager,
+                host: args.host,
+                ctrl_c: args.ctrl_c,
+                current_errors: args.current_errors,
+                name: args.call_info.name_tag,
+                raw_input: args.raw_input,
+            },
+            product,
+        )
+        .await
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Get the product of a list of numbers",
+            example: "echo [2 3 3 4] | math product",
+            result: Some(vec![UntaggedValue::int(72).into()]),
+        }]
+    }
+}
+
+fn to_byte(value: &Value) -> Option<Value> {
+    match &value.value {
+        UntaggedValue::Primitive(Primitive::Int(num)) => Some(
+            UntaggedValue::Primitive(Primitive::Filesize(convert_number_to_u64(&Number::Int(
+                num.clone(),
+            ))))
+            .into_untagged_value(),
+        ),
+        _ => None,
+    }
+}
+
+/// Calculate product of given values
+pub fn product(values: &[Value], name: &Tag) -> Result<Value, ShellError> {
+    let prod = reducer_for(Reduce::Product);
+
+    let first = values.get(0).ok_or_else(|| {
+        ShellError::unexpected("Cannot perform aggregate math operation on empty data")
+    })?;
+
+    match first {
+        v if v.is_filesize() => to_byte(&prod(
+            UntaggedValue::int(1).into_untagged_value(),
+            values
+                .iter()
+                .map(|v| match v {
+                    Value {
+                        value: UntaggedValue::Primitive(Primitive::Filesize(num)),
+                        ..
+                    } => UntaggedValue::int(*num as usize).into_untagged_value(),
+                    other => other.clone(),
+                })
+                .collect::<Vec<_>>(),
+        )?)
+        .ok_or_else(|| {
+            ShellError::labeled_error(
+                "could not convert to decimal",
+                "could not convert to decimal",
+                &name.span,
+            )
+        }),
+
+        v if v.is_none() => prod(
+            UntaggedValue::int(1).into_untagged_value(),
+            values
+                .iter()
+                .map(|v| match v {
+                    Value {
+                        value: UntaggedValue::Primitive(Primitive::Nothing),
+                        ..
+                    } => UntaggedValue::int(1).into_untagged_value(),
+                    other => other.clone(),
+                })
+                .collect::<Vec<_>>(),
+        ),
+        _ => prod(UntaggedValue::int(1).into_untagged_value(), values.to_vec()),
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::SubCommand;
+
+    #[test]
+    fn examples_work_as_expected() {
+        use crate::examples::test as test_examples;
+
+        test_examples(SubCommand {})
+    }
+}

crates/nu-cli/src/commands/math/reducers.rs

@@ -47,6 +47,7 @@ pub fn reducer_for(
         )),
         Reduce::Minimum => Box::new(|_, values| min(values)),
         Reduce::Maximum => Box::new(|_, values| max(values)),
+        Reduce::Product => Box::new(|_, values| product(values)),
     }
 }
 
@@ -54,6 +55,7 @@ pub enum Reduce {
     Summation,
     Minimum,
     Maximum,
+    Product,
     Default,
 }
 
@@ -133,3 +135,34 @@ pub fn min(data: Vec<Value>) -> Result<Value, ShellError> {
         tag: Tag::unknown(),
     })
 }
+
+pub fn product(data: Vec<Value>) -> Result<Value, ShellError> {
+    if data.is_empty() {
+        return Err(ShellError::unexpected(ERR_EMPTY_DATA));
+    }
+
+    let mut prod = UntaggedValue::int(1).into_untagged_value();
+    for value in data {
+        match value.value {
+            UntaggedValue::Primitive(_) => {
+                prod = match compute_values(Operator::Multiply, &prod, &value) {
+                    Ok(v) => v.into_untagged_value(),
+                    Err((left_type, right_type)) => {
+                        return Err(ShellError::coerce_error(
+                            left_type.spanned_unknown(),
+                            right_type.spanned_unknown(),
+                        ))
+                    }
+                };
+            }
+            _ => {
+                return Err(ShellError::labeled_error(
+                    "Attempted to compute the product of a value that cannot be multiplied.",
+                    "value appears here",
+                    value.tag.span,
+                ))
+            }
+        }
+    }
+    Ok(prod)
+}

docs/commands/math.md

@@ -9,6 +9,7 @@ Currently the following functions are implemented:
 * `math max`: Finds the maximum within a list of numbers or tables
 * `math median`: Finds the median of a list of numbers or tables
 * `math sum`: Finds the sum of a list of numbers or tables
+* `math product`: Finds the product of a list of numbers or tables
 
 However, the mathematical functions like `min` and `max` are more permissive and also work on `Dates`.
 
@@ -90,6 +91,11 @@ To get the average of the file sizes in a directory, simply pipe the size column
 ───┴──────────
 ```
 
+```shell
+> echo [2 3 3 4] | math product
+72
+```
+
 ### Dates
 
 ```shell