Issue 1787 (#1827)

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

@@ -2,9 +2,11 @@ use crate::commands::WholeStreamCommand;
 use crate::prelude::*;
 use crate::utils::data_processing::{reducer_for, Reduce};
 use nu_errors::ShellError;
-use nu_protocol::{ReturnSuccess, ReturnValue, Signature, UntaggedValue, Value};
+use nu_protocol::{Dictionary, ReturnSuccess, ReturnValue, Signature, UntaggedValue, Value};
 use num_traits::identities::Zero;
 
+use indexmap::map::IndexMap;
+
 pub struct Sum;
 
 impl WholeStreamCommand for Sum {
@@ -54,13 +56,40 @@ impl WholeStreamCommand for Sum {
 
 fn sum(RunnableContext { mut input, .. }: RunnableContext) -> Result<OutputStream, ShellError> {
     let stream = async_stream! {
-        let mut values = input.drain_vec().await;
+        let mut values: Vec<Value> = input.drain_vec().await;
-
         let action = reducer_for(Reduce::Sum);
 
-        match action(Value::zero(), values) {
+        if values.iter().all(|v| if let UntaggedValue::Primitive(_) = v.value {true} else {false}) {
-            Ok(total) => yield ReturnSuccess::value(total),
+            let total = action(Value::zero(), values)?;
+            yield ReturnSuccess::value(total)
+        } else {
+            let mut column_values = IndexMap::new();
+            for value in values {
+                match value.value {
+                    UntaggedValue::Row(row_dict) => {
+                        for (key, value) in row_dict.entries.iter() {
+                            column_values
+                                .entry(key.clone())
+                                .and_modify(|v: &mut Vec<Value>| v.push(value.clone()))
+                                .or_insert(vec![value.clone()]);
+                        }
+                    },
+                    table => {},
+                };
+            }
+
+            let mut column_totals = IndexMap::new();
+            for (col_name, col_vals) in column_values {
+                let sum = action(Value::zero(), col_vals);
+                match sum {
+                    Ok(value) => {
+                        column_totals.insert(col_name, value);
+                    },
                     Err(err) => yield Err(err),
+                };
+            }
+            yield ReturnSuccess::value(
+                UntaggedValue::Row(Dictionary {entries: column_totals}).into_untagged_value())
         }
     };
 

crates/nu-cli/src/utils/data_processing.rs

@@ -198,9 +198,20 @@ pub fn evaluate(
 }
 
 pub fn sum(data: Vec<Value>) -> Result<Value, ShellError> {
-    Ok(data
+    let mut acc = Value::zero();
-        .into_iter()
+    for value in data {
-        .fold(Value::zero(), |acc: Value, value| acc + value))
+        match value.value {
+            UntaggedValue::Primitive(_) => acc = acc + value,
+            _ => {
+                return Err(ShellError::labeled_error(
+                    "Attempted to compute the sum of a value that cannot be summed.",
+                    "value appears here",
+                    value.tag.span,
+                ))
+            }
+        }
+    }
+    Ok(acc)
 }
 
 fn formula(

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

@@ -1,6 +1,7 @@
 use nu_test_support::fs::Stub::FileWithContentToBeTrimmed;
 use nu_test_support::playground::Playground;
 use nu_test_support::{nu, pipeline};
+use std::str::FromStr;
 
 #[test]
 fn all() {
@@ -60,3 +61,52 @@ fn outputs_zero_with_no_input() {
         assert_eq!(actual.out, "0");
     })
 }
+
+#[test]
+fn compute_sum_of_individual_row() -> Result<(), String> {
+    let answers_for_columns = [
+        ("cpu", 88.257434),
+        ("mem", 3032375296.),
+        ("virtual", 102579965952.),
+    ];
+    for (column_name, expected_value) in answers_for_columns.iter() {
+        let actual = nu!(
+            cwd: "tests/fixtures/formats/",
+            format!("open sample-ps-output.json | select {} | sum | get {}", column_name, column_name)
+        );
+        let result =
+            f64::from_str(&actual.out).map_err(|_| String::from("Failed to parse float."))?;
+        assert_eq!(result, *expected_value);
+    }
+    Ok(())
+}
+
+#[test]
+fn compute_sum_of_table() -> Result<(), String> {
+    let answers_for_columns = [
+        ("cpu", 88.257434),
+        ("mem", 3032375296.),
+        ("virtual", 102579965952.),
+    ];
+    for (column_name, expected_value) in answers_for_columns.iter() {
+        let actual = nu!(
+            cwd: "tests/fixtures/formats/",
+            format!("open sample-ps-output.json | select cpu mem virtual | sum | get {}", column_name)
+        );
+        let result =
+            f64::from_str(&actual.out).map_err(|_| String::from("Failed to parse float."))?;
+        assert_eq!(result, *expected_value);
+    }
+    Ok(())
+}
+
+#[test]
+fn sum_of_a_row_containing_a_table_is_an_error() {
+    let actual = nu!(
+        cwd: "tests/fixtures/formats/",
+        "open sample-sys-output.json | sum"
+    );
+    assert!(actual
+        .err
+        .contains("Attempted to compute the sum of a value that cannot be summed."));
+}

crates/nu-protocol/src/value.rs

@@ -531,7 +531,8 @@ impl std::ops::Add for Value {
 
                 UntaggedValue::from(left.add(right)).into_value(tag)
             }
-            (_, _) => unimplemented!("Internal error: can't add non-primitives."),
+            (_, _) => UntaggedValue::Error(ShellError::unimplemented("Can't add non-primitives."))
+                .into_value(tag),
         }
     }
 }

tests/fixtures/formats/sample-ps-output.json

@@ -0,0 +1 @@
+[{"pid":10390,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":132112384,"virtual":4989624320},{"pid":10461,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":126992384,"virtual":4995346432},{"pid":10530,"name":"kworker/6:1-events","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":10593,"name":"kworker/1:1-mm_percpu_wq","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":10650,"name":"chrome","status":"Sleeping","cpu":8.026974,"mem":262434816,"virtual":5217419264},{"pid":10803,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":48173056,"virtual":542531584},{"pid":11191,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":124092416,"virtual":4975763456},{"pid":11210,"name":"kworker/7:0-events","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":11254,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":113070080,"virtual":4971659264},{"pid":11279,"name":"kworker/u16:0-events_unbound","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":11476,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":88993792,"virtual":4937097216},{"pid":12755,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":163397632,"virtual":5034328064},{"pid":12772,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":113561600,"virtual":4985073664},{"pid":14351,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":111861760,"virtual":4962754560},{"pid":17818,"name":"udisksd","status":"Sleeping","cpu":0.0,"mem":14409728,"virtual":402935808},{"pid":17815,"name":".gvfs-udisks2-v","status":"Sleeping","cpu":0.0,"mem":16199680,"virtual":585306112},{"pid":17831,"name":".gvfs-mtp-volum","status":"Sleeping","cpu":0.0,"mem":6393856,"virtual":454680576},{"pid":17836,"name":".gvfs-gphoto2-v","status":"Sleeping","cpu":0.0,"mem":7110656,"virtual":456966144},{"pid":17841,"name":".gvfs-afc-volum","status":"Sleeping","cpu":0.0,"mem":8585216,"virtual":537448448},{"pid":17846,"name":".gvfsd-trash-wr","status":"Sleeping","cpu":0.0,"mem":12767232,"virtual":577998848},{"pid":17856,"name":".gvfsd-network-","status":"Sleeping","cpu":0.0,"mem":13295616,"virtual":654110720},{"pid":17862,"name":".gvfsd-dnssd-wr","status":"Sleeping","cpu":0.0,"mem":7639040,"virtual":533233664},{"pid":17869,"name":"dconf-service","status":"Sleeping","cpu":0.0,"mem":5365760,"virtual":158957568},{"pid":18153,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":183738368,"virtual":5128962048},{"pid":23033,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":166035456,"virtual":5074878464},{"pid":24101,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":101224448,"virtual":4956262400},{"pid":24832,"name":"kworker/7:2-events","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":24912,"name":"kworker/5:2-events_power_efficient","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":25228,"name":"kworker/4:3-events","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":25678,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":117522432,"virtual":4970983424},{"pid":25706,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":30760960,"virtual":528375808},{"pid":26080,"name":"kworker/1:0-events","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":26818,"name":"kworker/2:0-events","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":26827,"name":"kworker/6:2-mm_percpu_wq","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":26832,"name":"kworker/0:2-mm_percpu_wq","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":26843,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":116621312,"virtual":4982403072},{"pid":27163,"name":"kworker/3:2-events","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":27800,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":128200704,"virtual":4965363712},{"pid":27820,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":54960128,"virtual":4895596544},{"pid":27898,"name":"kworker/3:0-mm_percpu_wq","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":27977,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":141930496,"virtual":4982546432},{"pid":28035,"name":"kworker/u16:1-events_unbound","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":28104,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":126853120,"virtual":5003902976},{"pid":28158,"name":"nu","status":"Sleeping","cpu":0.0,"mem":27344896,"virtual":870764544},{"pid":28236,"name":"chrome","status":"Sleeping","cpu":0.0,"mem":450560000,"virtual":5389582336},{"pid":29186,"name":"kworker/5:0-events","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":30140,"name":"kworker/u16:2-events_unbound","status":"Idle","cpu":0.0,"mem":0,"virtual":0},{"pid":30142,"name":"nu_plugin_core_","status":"Zombie","cpu":0.0,"mem":0,"virtual":0},{"pid":30356,"name":"sh","status":"Sleeping","cpu":0.0,"mem":3743744,"virtual":224092160},{"pid":30360,"name":"nu_plugin_core_ps","status":"Sleeping","cpu":80.23046000000001,"mem":6422528,"virtual":633016320}]

tests/fixtures/formats/sample-sys-output.json

@@ -0,0 +1,125 @@
+{
+    "host": {
+        "name": "Linux",
+        "release": "5.4.33",
+        "version": "#1-NixOS SMP Fri Apr 17 08:50:26 UTC 2020",
+        "hostname": "nixos",
+        "arch": "x86_64",
+        "uptime": 105126,
+        "sessions": [
+            "alexj"
+        ]
+    },
+    "cpu": {
+        "cores": 8,
+        "current ghz": 2.4200000000000004,
+        "min ghz": 0.39999999999999997,
+        "max ghz": 3.4000000000000004
+    },
+    "disks": [
+        {
+            "device": "/dev/disk/by-uuid/e9adff48-c37b-4631-b98b-eaec9b410ba3",
+            "type": "ext4",
+            "mount": "/",
+            "total": 483445473280,
+            "used": 121866776576,
+            "free": 336949624832
+        },
+        {
+            "device": "/dev/disk/by-uuid/e9adff48-c37b-4631-b98b-eaec9b410ba3",
+            "type": "ext4",
+            "mount": "/nix/store",
+            "total": 483445473280,
+            "used": 121866776576,
+            "free": 336949624832
+        },
+        {
+            "device": "/dev/sda3",
+            "type": "vfat",
+            "mount": "/boot",
+            "total": 534757376,
+            "used": 72650752,
+            "free": 462106624
+        }
+    ],
+    "mem": {
+        "total": 16256524000,
+        "free": 3082268000,
+        "swap total": 18874344000,
+        "swap free": 18874344000
+    },
+    "temp": [
+        {
+            "unit": "iwlwifi_1",
+            "temp": 42.0
+        },
+        {
+            "unit": "acpitz",
+            "temp": 53.00000000000001,
+            "critical": 103.0
+        },
+        {
+            "unit": "coretemp",
+            "label": "Core 1",
+            "temp": 52.00000000000001,
+            "high": 100.0,
+            "critical": 100.0
+        },
+        {
+            "unit": "coretemp",
+            "label": "Core 2",
+            "temp": 52.00000000000001,
+            "high": 100.0,
+            "critical": 100.0
+        },
+        {
+            "unit": "coretemp",
+            "label": "Package id 0",
+            "temp": 52.00000000000001,
+            "high": 100.0,
+            "critical": 100.0
+        },
+        {
+            "unit": "coretemp",
+            "label": "Core 3",
+            "temp": 51.00000000000001,
+            "high": 100.0,
+            "critical": 100.0
+        },
+        {
+            "unit": "coretemp",
+            "label": "Core 0",
+            "temp": 51.00000000000001,
+            "high": 100.0,
+            "critical": 100.0
+        },
+        {
+            "unit": "pch_skylake",
+            "temp": 48.00000000000001
+        }
+    ],
+    "net": [
+        {
+            "name": "wlp2s0",
+            "sent": 387642399,
+            "recv": 15324719784
+        },
+        {
+            "name": "lo",
+            "sent": 2667,
+            "recv": 2667
+        },
+        {
+            "name": "vboxnet0",
+            "sent": 0,
+            "recv": 0
+        }
+    ],
+    "battery": [
+        {
+            "vendor": "ASUSTeK",
+            "model": "ASUS Battery",
+            "cycles": 445
+        }
+    ]
+}