Add Count The Lines In A CSV Where A Column Is Empty as a Unix TIL

README.md

@@ -10,7 +10,7 @@ pairing with smart people at Hashrocket.
 
 For a steady stream of TILs, [sign up for my newsletter](https://crafty-builder-6996.ck.page/e169c61186).
 
-_1338 TILs and counting..._
+_1340 TILs and counting..._
 
 ---
 
@@ -1020,6 +1020,7 @@ _1338 TILs and counting..._
 
 - [Check Specific Arguments To Received Method](rspec/check-specific-arguments-to-received-method.md)
 - [Find Minimal Set Of Tests Causing A Flicker](rspec/find-minimal-set-of-tests-causing-a-flicker.md)
+- [Format Test Results As A JSON File](rspec/format-test-results-as-a-json-file.md)
 - [Run Tests With Documentation Formatting](rspec/run-tests-with-documentation-formatting.md)
 - [Use Specific Cache Store In A Single Test](rspec/use-specific-cache-store-in-a-single-test.md)
 
@@ -1256,6 +1257,7 @@ _1338 TILs and counting..._
 - [Configure cd To Behave Like pushd In Zsh](unix/configure-cd-to-behave-like-pushd-in-zsh.md)
 - [Copying File Contents To System Paste Buffer](unix/copying-file-contents-to-system-paste-buffer.md)
 - [Copying Nested Directories With Ditto](unix/copying-nested-directories-with-ditto.md)
+- [Count The Lines In A CSV Where A Column Is Empty](unix/count-the-lines-in-a-csv-where-a-column-is-empty.md)
 - [Count The Number Of Matches In A Grep](unix/count-the-number-of-matches-in-a-grep.md)
 - [Count The Number Of ripgrep Pattern Matches](unix/count-the-number-of-ripgrep-pattern-matches.md)
 - [Create A File Descriptor with Process Substitution](unix/create-a-file-descriptor-with-process-substitution.md)

rspec/format-test-results-as-a-json-file.md

@@ -0,0 +1,21 @@
+# Format Test Results As A JSON File
+
+The most common output format for RSpec test results is _progress_ which shows
+the dot (`.`) or `F` for each test pass and fail. RSpec supports other formats,
+including JSON.
+
+You'd typically want to use the JSON format when you want to programmatically
+work with the results. And the results would be most accessible if they ended
+up in a file.
+
+So, when formatting the results to JSON, we typically also want to specify an
+output file. We'll need to use two flags — `--format` and `--out`.
+
+```bash
+$ rspec --format json --out test_run_1.json
+```
+
+When this test run completes, we will have the results in JSON format in the
+newly created `test_run_1.json` file in the current directory.
+
+See `rspec --help` for more details.

unix/count-the-lines-in-a-csv-where-a-column-is-empty.md

@@ -0,0 +1,25 @@
+# Count The Lines In A CSV Where A Column Is Empty
+
+The [`xsv` utility](https://github.com/BurntSushi/xsv) is a fast way to analyze
+and work with CSV files from the command line.
+
+With the `search` subcommand, I can seach for lines that match a pattern and
+even narrow that search to focus on a selected column.
+
+For instance, to search for any lines where column 3 is empty:
+
+```
+$ xsv search -s 3 '^$' data.csv
+```
+
+The `-s 3` narrows the search to just column 3. The `'^$'` regex pattern
+matches on cells where there is the start character (`^`) and end character
+(`$`) with nothing in between, hence empty.
+
+I can then pipe that to `wc -l` to get a count of the number of empty lines.
+
+```
+$ xsv search -s 3 '^$' data.csv | wc -l
+```
+
+See `xsv search --help` for more details.