Regular Expressions. Validation. Split. Matching, ... ------------------------------------------------------------ Test RegEx at: http://www.regexr.com ------------------------------------------------------------ [0-9]+ ------------------------------------------------------------ [A-Z][a-z]* ------------------------------------------------------------ \s+ ------------------------------------------------------------ \S+ ------------------------------------------------------------ \w+ ------------------------------------------------------------ \W+ ------------------------------------------------------------ \+\d{1,3}([ -]*[0-9]){6,} +1-800-555-2468 +359 2 834-2334 +359888123456 (052) 343-434 ------------------------------------------------------------ ^\+\d{1,3}([ -]*[0-9]){6,}$ +359 2 123-456 is a match +359 (888) 123-456 is a NOT match ------------------------------------------------------------ Simplified Email Extraction Pattern: /[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,20}/gi ------------------------------------------------------------ var emailPattern = /^[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,20}$/i; console.log(emailPattern.test("test@abv.bg")); console.log(emailPattern.test("a.hills@gtx.de")); console.log(emailPattern.test("invalid@@mail")); console.log(emailPattern.test("err test@abv.bg")); ------------------------------------------------------------ var towns = "Sofia, Varna,Pleven, Veliko Tarnovo; Paris – London––Viena\n\n Пловдив|Каспичан"; console.log(towns.split(/\W+/)); // incorrect console.log(towns.split(/\s*[.,|;\n\t–]+\s*/)); ------------------------------------------------------------ var text = "I was born at 14-Jun-1980. Today is 14-Mar-2015. Next year starts at 1-Jan-2016 and ends at 31-Dec-2016."; var dateRegex = /\d{1,2}-\w{3}-\d{4}/gm; console.log(text.match(dateRegex));

1. Regular Expressions
… and Their Place in the QA Engineer's Life
Svetlin Nakov
Manager Training
and Inspiration
Software University
http://softuni.bg

2. What are Regular Expressions?
• Regular expressions (regex)
– Match text by pattern
• Patterns are defined by special syntax, e.g.
– [0-9]+ matches non-empty sequence of digits
– [A-Z][a-z]* matches a capital + small letters
– s+ matches whitespace (non-empty)
• S+ matches non-whitespace
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3. 3
DEMO
www.regexr.com

4. More Patterns
• d+ matches digits
– D+ matches non-digits
• w+ matches letters (Unicode)
– W+ matches non-letters
• +d{1,3}([ -]*[0-9]){6,} matches
international phone, e.g. +359 2 123-456
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5. 5
DEMO
www.regexr.com

6. Validation by Regex
• ^ matches start of text
• $ matches end of text
• ^+d{1,3}([ -]*[0-9]){6,}$ validates
international phone
• +359 2 123-456 is a valid phone
• +359 (888) 123-456 is a invalid phone
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7. 7
DEMO
www.regexr.com

8. Regex Literals
• The classical (Perl syntax) is:
– /<regex>/<options>
• Examples:
– /[a-z]+/gi matches all non-empty sequences
of Latin letters, case-insensitively
– /[a-z0-9._%+-]+@[a-z0-9.-]+.[a-z]{2,20}/gi
matches emails (simplified pattern)
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9. 9
DEMO
www.debuggex.com

10. Some JS Code: Validation
var emailPattern =
/^[a-z0-9._%+-]+@[a-z0-9.-]+.[a-z]{2,20}$/i;
console.log(emailPattern.test("test@abv.bg"));
console.log(emailPattern.test("a.hills@gtx.de"));
console.log(emailPattern.test("invalid@@mail"));
console.log(emailPattern.test("err test@abv.bg"));
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11. Some JS Code: Split
var towns = "Sofia, Varna,Pleven, Veliko Tarnovo;
Paris – London––Vienann Пловдив|Каспичан";
console.log(towns.split(/W+/)); // incorrect
console.log(towns.split(/s*[.,|;nt–]+s*/));
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12. Some JS Code: Match
var text = "I was born at 14-Jun-1980. Today is
14-Mar-2015. Next year starts at 1-Jan-2016 and
ends at 31-Dec-2016.";
var dateRegex = /d{1,2}-w{3}-d{4}/gm;
console.log(text.match(dateRegex));
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13. Regex for QA Engineers
• Why should a QA understand regex?
– Validation  prepare regex for developers
– Write automation testing scripts
• E.g. find a text on the page by regex
– Parse a text, extract info, split data, …
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14. Resources
• Play with regex:
– http://www.regexr.com
– https://regex101.com
• Visual regex debugger:
– https://www.debuggex.com
• Regex explained (in Bulgarian)
– http://goo.gl/NbBIPe
–
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15. Resources (2)
• Interactive Regex Tutorial
– http://regexone.com
• Regex @ W3Schools
– http://w3schools.com/jsref/jsref_obj_regexp.asp
• Regex Tutorial (for Java)
– vogella.com/tutorials/JavaRegularExpressions/article.html
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16. Regular Expressions
Questions?
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