How Google Tests Software - Part Seven

【转】How Google Tests Software - Part Seven

By James Whittaker
The Life of a TE
The Test Engineer is a newer role within Google than either SWEs or SETs. As such, it is a role still in the process of being defined. The current generation of Google TEs are blazing a trail which will guide the next generation of new hires for this role. It is the process that is emerging as the best within Google that we present here.
Not all products require the services of a TE. Experimental efforts and early stage products without a well-defined mission or user story are certainly projects that won’t get a lot of TE attention. If the product stands a good chance of being cancelled (in the sense that as a proof of concept it fails to pass muster) or has yet to engage users or have a well defined set of features, testing it is largely something that should be done by the people developing it.
Even if it is clear that a product is going to get shipped, Test Engineers have little to do early in the development cycle when features are still in flux and the final feature list and scope is undetermined. Overinvesting in testing too early can mean a lot of things get thrown away. Likewise, early testing planning requires fewer test engineers than later cycle exploratory testing when the product is close to final form and the hunt for missed bugs has a greater urgency.
The trick in staffing a project with Test Engineers has to do with risk and return on investment. Risk to the customer and to the enterprise means more testing effort and requires more TEs. But that effort needs to be in proportion to the potential return. We need the right number of TEs and we need them to engage at the right time and with the right impact.
Once engaged, TEs do not have to start from scratch. There is a great deal of test engineering and quality-oriented work performed by SWEs and SETs which is the starting point for additional TE work. The initial engagement of the TE is to decide things such as:
· Where are the weak points in the software?
· What are the security, privacy, performance and reliability concerns?
· Do all the primary user scenarios work as expected? For all international audiences?
· Does the product interoperate with other products (hardware and software)?
· In the event of a problem, how good are the diagnostics?
All of this combines to speak to the risk profile of releasing the software in question. TEs don’t necessarily do all of this work, but they ensure that it gets done and they leverage the work of others is assessing where additional work is required. Ultimately, test engineers are paid to protect users and the business from bad design, confusing UX, functional bugs, security and privacy issues and so forth. At Google, TEs are the only people on a team whose full-time job is to look at the product or service holistically for weak points. As such, the life of a Test Engineer is much less prescriptive and formalized than that of an SET. TE’s are asked to help on projects in all stages of readiness: everything from the idea stage to version 8, or even watching over a deprecated or “mothballed” project. Often, a single TE will even span multiple projects particularly those with specialty type skills like security.
Obviously, the work of a TE varies greatly depending on the project. Some TE’s spend much of their time programming, much like an SET, but with more of a focus on end-to-end user scenarios. Other TE's take existing code and designs determine failure modes and look for errors that will cause those failures. In such a role a TE might modify code but not create it from scratch. TE's must be more systematic and thorough in their test planning and completeness with a focus on the actual usage and system experience. TE's excel at dealing with ambiguity in requirements and at reasoning and communicating about fuzzy problems.
Successful TEs accomplish all this while navigating the sensitivities and sometimes strong personalities of the development and product team members. When weak points are found, test engineers happily break the software, and drive to get these issues resolved with the SWEs, PMs, and SETs.
Such a job description is a frightening prospect given the mix of technical skill, leadership, and deep product understanding and without proper guidance it is a role in which many would expect to fail. But at Google a strong community of test engineers has emerged to counter this. Of all job functions, the TE role is perhaps the best peer supported role in the company and the insight and leadership required to perform it successfully means that many of the top test managers in the company come from the TE ranks.
There is a fluidity to the work of a Google Test Engineer that belies any prescriptive process for engagement. TE’s can enter a project at any point and must assess the state of the project, code, design, and users quickly and decide what to focus on first. If the project is just getting started, test planning is often the first order of business. Sometimes TEs are pulled in late in the cycle to evaluate whether a project is ready for ship or if there are any major issues before an early ‘beta’ goes out. If they are brought into a newly acquired application or one in which they have little prior experience, they will often start doing some exploratory testing with little to no planning. Sometimes projects haven’t been released for quite a while and just need some touchups/security fixes, or UX updates—calling for an even different approach. One size rarely fits all for TEs at Google.