docs(manual): split testing into multiple chapters (#11067)

Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>

1 files changed, 36 insertions, 0 deletions

diff --git a/docs/testing/coverage.md b/docs/testing/coverage.md
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+# Test coverage
+
+Deno will collect test coverage into a directory for your code if you specify
+the `--coverage` flag when starting `deno test`.
+
+This coverage information is acquired directly from the JavaScript engine (V8)
+which is very accurate.
+
+This can then be further processed from the internal format into well known
+formats by the `deno coverage` tool.
+
+```bash
+# Go into your project's working directory
+git clone https://github.com/oakserver/oak && cd oak
+
+# Collect your coverage profile with deno test --coverage=<output_directory>
+deno test --coverage=cov_profile
+
+# From this you can get a pretty printed diff of uncovered lines
+deno coverage cov_profile
+
+# Or generate an lcov report
+deno coverage cov_profile --lcov > cov_profile.lcov
+
+# Which can then be further processed by tools like genhtml
+genhtml -o cov_profile/html cov_profile.lcov
+```
+
+By default, `deno coverage` will exclude any files matching the regular
+expression `test\.(js|mjs|ts|jsx|tsx)` and only consider including specifiers
+matching the regular expression `^file:` - ie. remote files will be excluded
+from coverage report.
+
+These filters can be overridden using the `--exclude` and `--include` flags. A
+module specifier must _match_ the include_regular expression and _not match_ the
+exclude_ expression for it to be a part of the report.