Wrote Part 3 section 1

Author: AutomationPanda

workshop/3-assertions.md

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+# Part 3: Writing assertions
+
+Part 3 of the workshop focuses on making assertions about the result page after performing a search.
+Waiting becomes a much bigger concern for these steps, but Playwright makes it easy.
+
+
+## Checking the search field
+
+After performing a search, our test case must check three things on the result page.
+According to the step, "Then the search result query is the phrase",
+the first thing to check is that the search input field at the top of the result page contains the search phrase.
+
+Here's the inspection panel for the search input element on the result page:
+
+![Inspecting the result search input element](images/inspect-result-search-input.png)
+
+This element also has an ID,
+so we can use the `#search_form_input` selector to uniquely identify it.
+
+To get the textual value inside this input element,
+you might think that we should use the
+[`inner_text`](https://playwright.dev/python/docs/api/class-page#page-inner-text) method
+or the [`text_content`](https://playwright.dev/python/docs/api/class-page#page-text-content) method.
+However, neither of these are correct.
+To get the value of an input element, you need to get its `value` attribute.
+Thankfully, Playwright provides a convenient method named
+[`input_value`](https://playwright.dev/python/docs/api/class-page#page-input-value) to get this.
+
+Add the following line to the test case:
+
+```python
+    assert 'panda' == page.input_value('#search_form_input')
+```
+
+This line will get the input value from the target element and assert that it is equal to the original search phrase.
+
+The full test case should now look like this:
+
+```python
+def test_basic_duckduckgo_search(page):
+
+    # Given the DuckDuckGo home page is displayed
+    page.goto('https://www.duckduckgo.com')
+
+    # When the user searches for a phrase
+    page.fill('#search_form_input_homepage', 'panda')
+    page.click('#search_button_homepage')
+
+    # Then the search result query is the phrase
+    assert 'panda' == page.input_value('#search_form_input')
+
+    # And the search result links pertain to the phrase
+    # And the search result title contains the phrase
+    pass
+```
+
+Hold on, do we have a race condition here?
+After calling `page.click(...)`, the browser will load the result page,
+but elements on the result page need time to be ready for interaction.
+Our test does nothing explicit to wait for the result page to load before trying to interact with the search input element.
+Is this a problem?
+
+Thankfully, in this case, there is no problem.
+Playwright automatically waits for elements to be ready before interacting with them.
+So, even though the test does not perform any *explicit* waiting for the result page,
+the `input_value` method performs *implicit* waiting for the element to be ready.
+Check the [Auto-waiting](https://playwright.dev/python/docs/actionability) page
+for a full list of actionability checks for each interaction.
+
+Rerun the test using the same pytest command (`python3 -m pytest tests --headed --slowmo 1000).
+This time, you should see the result page for a good second or two before the browser window closes.
+The test should still pass.
+
+
+## Checking the result links
+
+TBD
+
+
+## Checking the title
+
+TBD